Auxiliary chamber and display device with improved contaminant removal

Information

  • Patent Grant
  • 6541912
  • Patent Number
    6,541,912
  • Date Filed
    Monday, July 26, 1999
    25 years ago
  • Date Issued
    Tuesday, April 1, 2003
    21 years ago
Abstract
An apparatus for removing contaminants from a display device is disclosed. In one embodiment, an auxiliary chamber is adapted to be coupled to a surface of a display device such that contaminants within the display device can travel from the display device into the auxiliary chamber. A getter is disposed in the auxiliary chamber. The getter is adapted to capture the contaminants once the contaminants travel from the display device into the auxiliary chamber. In other embodiments, the getter is disposed in the border region surrounding the active area of the display.
Description




FIELD OF THE INVENTION




The present claimed invention relates to the field of flat panel displays. More particularly, the present claimed invention relates to an auxiliary chamber and display device with improved contaminant removal.




BACKGROUND ART




Display devices such as, for example, flat panel display devices typically utilize an evacuated environment during operation. In a field emission-type display device, field emitters located on a cathode emit electrons which are directed towards respective pixel or sub-pixel regions on a faceplate. In such a device, it is imperative that the region between the faceplate and the cathode (i.e. the active environment) remain free of contaminants so that the electrons can travel unimpeded from the cathode to the faceplate. As yet another concern, if certain contaminants are present in the active environment between the cathode and the faceplate, certain features, such as the field emitters may be damaged.




With reference now to Prior Art

FIG. 1

, a side sectional view of a display device


100


employing a conventional contaminant reduction approach is shown. Specifically, Prior Art

FIG. 1

shows a backplate or cathode


102


secured to a faceplate


104


via a sealing frame


106


. The active environment is the region located between cathode


102


and faceplate


104


. Field emitters, typically shown as


108


, are coupled to cathode


102


and are disposed within the active environment. In the conventional approach of Prior Art

FIG. 1

, a getter material


110


is also coupled to the cathode and is disposed within the active environment. The getter material is intended to capture contaminant particles which remain in the active environment after an evacuation process. The getter material is also intended to capture contaminant particles which are generated during operation of display device


100


.




Unfortunately, the conventional approach of Prior Art

FIG. 1

has significant drawbacks associated therewith. By locating getter material


110


within the active environment, region


112


is no longer available for use. That is, such a prior art approach reduces or compromises the amount of space which is available to be utilized by features such as, for example, field emitters. Additionally, by placing getter material


110


within the active environment, such a prior art approach deleteriously subjects the active environment, and hence field emitters


108


, to the hazardous getter material


110


. As a result, field emitters


108


are often degraded or damaged due to their close proximity to getter material


110


.




With reference now to Prior Art

FIG. 2

, a side sectional view of display device


100


employing another conventional approach in an attempt to reduce contaminants is shown. In this approach a pump-out tube is coupled directly to the active environment. The pump-out tube is used to facilitate evacuation of display device


100


, and, hence, remove contaminants therefrom. Once again, such a conventional approach has severe drawbacks associated therewith. Attaching tubulation directly to the active environment of display device


100


greatly complicates the process of manufacturing display device


100


. Additionally, the increased complexity associated with attaching the tubulation directly to display device


100


adds additional cost to the manufacturing process. Furthermore, the potential for defects in display device


100


is heightened by attaching tubulation


114


directly to display device


100


.




Referring still to Prior Art

FIG. 2

, conventional tubulation such as tubulation


114


significantly alters and increase the “envelope” of display device


100


. The envelope of display device


100


refers roughly to the amount of space occupied by the display device


100


. In Prior Art

FIG. 2

, the envelope of display device


100


is shown by dotted line


116


. As a result of protruding tubulation


114


, display device


100


must be allotted a larger area in which to operate. It will be seen from Prior Art

FIG. 2

, that the increased area or envelope


116


required by tubulation


114


may restrict or limit the locations and environments in which display device


100


can be used.




With reference next to Prior Art

FIG. 3

, a side sectional view of display device


100


employing another conventional approach in an attempt to reduce contaminants is shown. In this conventional approach, tubulation


118


is again attached directly to the active environment of display device


100


. As still another drawback, tubulation


118


extends beyond the edge of display device. As result, prior art tubulation


118


often interferes with the sealing process used to secure cathode


102


and faceplate


104


together. More specifically, during a laser sealing process, for example, the laser beam or beams must contact the entire periphery of display device


100


. In the configuration shown in Prior Art

FIG. 3

, tubulation


118


can obstruct the laser beam or beams, thereby “shadowing” a portion of the periphery of display device


100


. As a result, the seal between cathode


102


and faceplate


104


can be compromised, or the sealing process must be altered to accommodate tubulation


118


.




Thus, a need exists for an apparatus which removes contaminants from a display device without compromising the usable amount of space available within the display device. A further need exists for an auxiliary chamber which meets the above listed needs but which does not deleteriously expose features of the display device to getter material. Still another need exists for an auxiliary chamber which meets the above-listed needs but which does not significantly increase or alter the overall dimensions of the display device. Still another need exists for an apparatus that has improved contaminant particle removal.




SUMMARY OF INVENTION




The present invention provides an apparatus which removes contaminants from a display device without compromising the usable amount of space available within the display device. The present invention also provides an auxiliary chamber which realizes the above listed accomplishment and which does not deleteriously expose features of the display device to getter material. The present invention further provides an auxiliary chamber which achieves the above-listed accomplishments but which does not significantly increase or alter the overall dimensions of the display device. The present invention also provides an apparatus with improved contaminant particle removal.




Specifically, the present invention provides an apparatus for removing contaminants from a display device using an auxiliary chamber, and a method for attaching the auxiliary chamber to the display device. In one embodiment, an auxiliary chamber is adapted to be coupled to a surface of a display device. The auxiliary chamber is adapted to be coupled to the surface of the display device such that contaminants within the display device can travel from the display device into the auxiliary chamber. The auxiliary chamber further includes a getter which is disposed therein. The getter is adapted to capture the contaminants once the contaminants travel from the display device into the auxiliary chamber. In so doing, the present invention eliminates the need for getter material to be placed within the active area of the display device. As a result, the present invention increases the usable amount of space available within the display device. This extra space can then be utilized by features such as, for example, additional field emitters.




In another embodiment, the present invention provides method for attaching an auxiliary chamber to a display device. In this embodiment, the present invention first conditions a surface of a display device such that a conditioned surface of the display device is generated. This conditioned surface of the display device is thereby adapted to have an auxiliary chamber bonded thereto. Next, the present invention conditions a surface of the auxiliary chamber such that a conditioned surface of the auxiliary chamber is generated. In so doing, the conditioned surface of the auxiliary chamber is adapted to be bonded to the conditioned surface of the display device. After the conditioning steps, the present invention bonds the conditioned surface of the auxiliary chamber to the conditioned surface of the display device.




In yet another embodiment, an auxiliary chamber is disclosed that includes a cylindrical housing. Cylindrical rings of non evaporable getter material are disposed within the cylindrical housing around a centrally disposed conductive element. In another embodiment, an auxiliary chamber is disclosed that houses a barium flash bulb.




The present invention also provides various apparatus that provide for improved contaminant particle removal. In one embodiment, improved particle removal is accomplished using a metal film that forms a surface having low thermal emissivity. In another embodiment, a carbon felt structure is used to achieve improved contaminant particle removal. In yet another embodiment, a pre-flashed getter capsule is used. Another embodiment discloses the use of RF coils for selectively activating getter material. In still another embodiment, various configurations of a planar evaporable getter are used.




These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments which are illustrated in the various drawing figures.











BRIEF DESCRIPTION OF THE DRAWINGS




The accompanying drawings, which are incorporated in and form a part of this specification, illustrates embodiments of the invention and, together with the description, serve to explain the principles of the invention:




PRIOR ART

FIG. 1

is a side sectional view of a display device employing a conventional contaminant reduction approach.




PRIOR ART

FIG. 2

is a side sectional view of a display device employing another approach used in an attempt to reduce contaminants.




PRIOR ART

FIG. 3

is a side sectional view of a display device having tubulation which protrudes beyond the edge of the display device.





FIG. 4

is a side sectional view of a display device having an auxiliary chamber coupled thereto in accordance with one embodiment of the present claimed invention.





FIG. 5

is a perspective view of the embodiment of

FIG. 4

in accordance with one embodiment of the present claimed invention.





FIG. 6A

is a schematic representation of getter material disposed on a bundled filament in accordance with one embodiment of the present claimed invention.





FIG. 6B

is a schematic representation of getter material disposed on a filament arranged in a lattice configuration in accordance with one embodiment of the present claimed invention.





FIG. 6C

is a schematic representation of getter material disposed on a plurality of separately bundled filaments in accordance with one embodiment of the present claimed invention.





FIG. 6D

is a schematic representation of getter material disposed on a plurality of filaments arranged in separate lattice configurations in accordance with one embodiment of the present claimed invention.





FIG. 7

is a side sectional view of a display device having an auxiliary chamber coupled thereto wherein the auxiliary chamber has tubulation projecting therefrom in accordance with one embodiment of the present claimed invention.





FIG. 8

is a side sectional view of a display device having an auxiliary chamber coupled thereto wherein the auxiliary chamber has bent tubulation projecting therefrom in accordance with one embodiment of the present claimed invention.





FIG. 9

is a side sectional view of a display device having an auxiliary chamber coupled thereto wherein the auxiliary chamber has sealed tubulation projecting therefrom in accordance with one embodiment of the present claimed invention.





FIG. 10

is a side sectional view of a display device having an auxiliary chamber coupled thereto wherein the auxiliary chamber is plug sealed in accordance with one embodiment of the present claimed invention.





FIG. 11

is a flow chart of steps performed to attach an auxiliary chamber to surface of a display device in accordance with one embodiment of the present claimed invention.





FIG. 12

is a flow chart of steps performed to condition the surface of a display device in accordance with one embodiment of the present claimed invention.





FIG. 13

is a flow chart of steps performed to condition the surface of an auxiliary chamber in accordance with one embodiment of the present claimed invention.





FIG. 14

is a flow chart of steps performed to bond a conditioned surface of an auxiliary chamber to a conditioned surface of a display device in accordance with one embodiment of the present claimed invention.





FIG. 15

is a flow chart of steps performed to attach an auxiliary chamber to surface of a display device using an adhesive in accordance with one embodiment of the present claimed invention.





FIG. 16A

is a side sectional view of a display device having an auxiliary chamber in a compressed state coupled thereto wherein the auxiliary chamber has a variable volume in accordance with one embodiment of the present claimed invention.





FIG. 16B

is a side sectional view of a display device having an auxiliary chamber in an expanded state coupled thereto wherein the auxiliary chamber has a variable volume in accordance with one embodiment of the present claimed invention.





FIG. 17A

is a perspective view of an auxiliary chamber that includes a cylindrical housing in accordance with one embodiment of the present claimed invention.





FIG. 17B

is a side sectional view of an auxiliary chamber that includes a cylindrical housing in accordance with one embodiment of the present claimed invention.





FIG. 17C

is a bottom view of an auxiliary chamber that includes a spiral of NEG material in accordance with one embodiment of the present claimed invention.





FIG. 17D

is a perspective view of auxiliary chambers attached to a surface of a display in accordance with one embodiment of the present claimed invention.





FIG. 17E

is a perspective view of an auxiliary chamber that includes a cylindrical housing and tubulation in accordance with one embodiment of the present claimed invention.





FIG. 17F

is a side cut away view of an auxiliary chamber that includes a cylindrical housing and a high voltage anode feed-through in accordance with one embodiment of the present claimed invention.





FIG. 18

is a side sectional view of an auxiliary chamber within which a flash bulb is disposed in accordance with one embodiment of the present claimed invention.





FIG. 19

is a side sectional view of a display device having an auxiliary chamber coupled thereto and having a low emissivity surface and a high emissivity surface in accordance with one embodiment of the present claimed invention.





FIG. 20

is a side sectional view of a display device having a low emissivity surface and a high emissivity surface in accordance with one embodiment of the present claimed invention.





FIG. 21A

is a side sectional view of a display device having an auxiliary chamber coupled thereto and having a carbon felt structure disposed within the auxiliary chamber in accordance with one embodiment of the present claimed invention.





FIG. 21B

is a side sectional view of a display device within which a carbon felt structure is disposed in accordance with one embodiment of the present claimed invention.





FIG. 22

is a top sectional view of an auxiliary chamber within which a support and two getters are disposed in accordance with one embodiment of the present claimed invention.





FIG. 23A

is a side sectional view of a pre-flashed getter capsule in accordance with one embodiment of the present claimed invention.





FIG. 23B

is a side sectional view of a pre-flashed getter capsule formed within an auxiliary chamber in accordance with one embodiment of the present claimed invention.





FIG. 23C

is a top sectional view of a pre-flashed getter capsule formed within an auxiliary chamber that includes support structures that are posts in accordance with one embodiment of the present claimed invention.





FIG. 23D

is a top sectional view of a pre-flashed getter capsule formed within an auxiliary chamber that includes support structures that are ribs in accordance with one embodiment of the present claimed invention.





FIG. 24

is a schematic view of an assembly that includes RF coils and that is disposed in an auxiliary chamber in accordance with one embodiment of the present claimed invention.





FIG. 25

is a schematic view of display having two getters disposed therein in accordance with one embodiment of the present claimed invention.





FIG. 26A

is a side sectional view of a getter that includes barium aluminum in accordance with one embodiment of the present claimed invention.





FIG. 26B

is a perspective view of a getter that includes a nickel substrate having channels in accordance with one embodiment of the present claimed invention.





FIG. 26C

is a perspective view of a getter that includes a nickel substrate having circular cavities in accordance with one embodiment of the present claimed invention.





FIG. 26D

is a side sectional view of a display within which two getters are disposed in accordance with one embodiment of the present claimed invention.





FIG. 26E

is a side sectional view of a display within which three getters are disposed in accordance with one embodiment of the present claimed invention.











The drawings referred to in this description should be understood as not being drawn to scale except if specifically noted.




DESCRIPTION OF THE PREFERRED EMBODIMENTS




Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present invention.




With reference now to

FIG. 4

, a side sectional view of a display device


400


having an auxiliary chamber


408


coupled thereto is shown. In the present embodiment, a backplate/cathode


402


is secured to a faceplate


404


using a sealing frame


406


. Although a sealing frame is recited in the present embodiment, the present invention is also well suited to embodiments employing any of numerous methods and devices to secure cathode


402


and faceplate


404


together. Additionally, display device


400


of the present is a flat panel display device, however, the present invention is well suited for use in any device in which contaminant reduction or containment is desired. Furthermore, display device


400


of the present embodiment may contain numerous features such as, for example, field emitters, pixel regions, spacer structures, and the like, which are not shown in

FIG. 4

for purposes of clarity. Also, in the present embodiment, auxiliary chamber


408


is coupled to backplate/cathode


402


of display device


400


. The present invention is, however, also well suited to an embodiment in which auxiliary chamber


408


is coupled to a portion of display device


400


other than backplate/cathode


402


.




Referring still to

FIG. 4

, an auxiliary chamber


408


is shown coupled to a surface of display device


400


in accordance with the present claimed invention. More particularly, in the embodiment of

FIG. 4

, auxiliary chamber


408


is coupled to the outer surface of cathode


402


. Auxiliary chamber


408


of the present embodiment has a getter


410


disposed therein. Also, in the present embodiment, auxiliary chamber


408


is disposed above small openings, typically shown as


412


. Openings


412


extend completely through the surface of cathode


402


to the active environment of display device


400


. By placing auxiliary chamber


408


above small openings


412


, contaminants within the active environment of display device


400


can travel through openings


412


, into auxiliary chamber


408


, and be captured by getter


410


.




With reference now to

FIG. 5

, a perspective view of the present embodiment is shown. In the present embodiment, auxiliary chamber


408


extends across the entire length of cathode


402


(i.e. one side to another side of cathode


402


), and auxiliary chamber is disposed above a plurality of holes


412


which extend through cathode


402


. Although such a configuration is shown in the present embodiment, the present invention is also well suited to various other configurations. Alternate configurations include, for example, configuring auxiliary chamber


408


to extend only partially across the surface of cathode


402


, configuring auxiliary chamber


408


to cover a larger portion of the surface of cathode


402


, configuring auxiliary chamber


408


to cover a smaller portion of the surface of cathode


402


, and the like. Additionally, the present invention is also well suited to an embodiment in which a plurality of auxiliary chambers are coupled to cathode


402


.




With reference again to

FIG. 4

, auxiliary chamber


408


of the present embodiment has an extremely low profile. That is, unlike prior art devices (see e.g. device


114


of Prior Art FIG.


2


), auxiliary chamber


408


of the present embodiment does not significantly increase or alter the overall dimensions of display device


400


. Thus, the “envelope” of display device


400


(shown by dotted line


116


) is not significantly affected by the addition of auxiliary chamber


408


. Therefore, unlike many conventional devices, auxiliary chamber


408


does not restrict or limit the locations and environments in which display device


400


can be used.




In the present embodiment, auxiliary chamber


408


is formed of any of various materials or combinations of material. In one embodiment, auxiliary chamber


408


is formed of glass. In another embodiment of the present invention auxiliary chamber


408


is formed of ceramic material such as, for example, alumina. Although these specific materials are recited herein, the present invention is well suited to forming auxiliary chamber out of various other materials such as metals, composites, plastics, and the like. The embodiment formed of ceramic material has several advantages associated therewith. For instance, in one embodiment when using ceramic material, auxiliary chamber


408


is formed using an extrusion process. In another embodiment when using ceramic material, auxiliary chamber


408


is formed using a molding process. In still another embodiment when using ceramic material, auxiliary chamber


408


is formed using a pressing process. In yet another embodiment when using ceramic material, auxiliary chamber


408


is formed using a lamination process. These aforementioned fabrication process greatly simplify the task of forming auxiliary chamber


408


, reduce costs associated with fabricating auxiliary chamber


408


, and improve the robustness of auxiliary chamber


408


. Additionally, heat distribution is improved in an embodiment in which auxiliary chamber is formed of ceramic material. This improved heat distribution is particularly advantageous during a getter activation process to be described in detail below. Specifically, by readily and evenly distributing heat, a ceramic auxiliary chamber


408


is not subject to severe heat induced stresses which can occur during, for example, getter activation. Because the present invention includes both ceramic and non-ceramic embodiments, the following discussion will pertain to both the ceramic and the non-ceramic embodiments unless specifically noted otherwise.




With reference still to

FIG. 4

, the present embodiment disposes getter


410


within auxiliary chamber


408


. Unlike conventional approaches, by locating getter


410


within auxiliary chamber, the present embodiment does not reduce or compromise the amount of space within the active environment which is available to be utilized by features such as, for example, field emitters. Furthermore, by placing getter


410


within auxiliary chamber


408


, the present embodiment does not deleteriously subject the active environment, and hence the field emitters, to the hazardous getter


410


. Although such an arrangement is recited in the present embodiment, the present invention is also well suited to an embodiment in which additional getter is disposed within or proximate to the active environment of display device


400


.




In one embodiment, getter


410


is comprised of evaporable getter such as, for example, barium, titanium, and the like. In another embodiment, getter


410


is comprised of a non-evaporable getter. In one embodiment, getter


410


includes barium rings. In still another embodiment, getter


410


is comprised of a combination of evaporable getter and non-evaporable getter. It will be understood that in certain embodiments of the present invention getter


410


must be activated. The present invention is well suited to accommodating any of the various getter activation processes well known in the art.




With reference now to

FIG. 6A

, a schematic representation of getter material disposed on a bundled filament


600


in accordance with one embodiment of the present claimed invention is shown. In this embodiment, getter material such as, for example, barium is coated on a filament. In the present embodiment, bundled filament


600


is comprised of tantalum, however, the present embodiment is also well suited to the use of various other filament materials, such as, for example, titanium, tungsten, a tantalum-titanium alloy, and the like. When exposed to heat, bundled filament


600


disperses or “flashes” or sublimates the getter material coated thereon throughout the interior surface of auxiliary chamber


408


. In the present embodiment, bundled filament


600


is exposed to an rf (radio frequency) heating source, a laser heating source, and the like.




Referring still to

FIG. 6A

, several substantial advantages are realized by the present embodiment. When flashed or heated, bundled filament


600


disperses the getter material widely and evenly throughout the interior surface of auxiliary chamber


408


. That is, many prior art approaches “throw” getter mate rial only very near an original source of the getter material. Thus, bundled filament


600


provides a substantial disbursement improvement over conventional getter distribution methods. Bundled filament


600


is also capable of being very long and tortuous, filling the internal space of auxiliary chamber


408


, and thereby containing more getter material than current getter source devices provide. Additionally, after the disbursement of the getter material, the filament remains within auxiliary chamber. The filament, along with the interior surface of auxiliary chamber


408


will have getter material dispersed thereon. The presence of the filament increases the surface area which is available to be coated with getter. Thus, gettering capabilities are enhanced in the present embodiment. Also, bundled filament


600


will heat, flash, or sublimate quickly, and distribute the heat evenly throughout the interior region of auxiliary chamber


408


, thereby exposing auxiliary chamber


408


and cathode


402


to minimal thermal shock.




As yet another advantage of the embodiment of

FIG. 6A

, bundled filament


600


can be prepared as a subassembly and then be disposed within auxiliary chamber


408


when desired. This manufacturing flexibility provides a substantial improvement over typical prior art getter sources. Furthermore, because of its extremely low mass (and, hence, minimal heat transfer), bundled filament


600


can be located within auxiliary chamber


408


directly on the surface of cathode


402


and/or directly against the interior surface of auxiliary chamber


408


. This versatility in the placement of bundled filament


600


substantially eases the burden of precise getter source mounting associated with conventional getter distribution methods.




Referring now to

FIG. 6B

, a schematic representation of getter material disposed on a filament arranged in a lattice configuration in accordance with one embodiment of the present claimed invention is shown. The filament is arranged in a lattice configuration to produce a “latticed filament”


602


wherein the various rows and columns of the latticed filament


602


do not contact each other at respective intersections thereof. The present embodiment is formed and functions similarly to the embodiment of FIG.


6


A. That is, getter material such as, for example, barium is coated on a filament. In the present embodiment, latticed filament


602


is comprised of tantalum, however, the present embodiment is also well suited to the use of various other filament materials, such as, for example, titanium, tungsten, a tantalum-titanium alloy, and the like. When exposed to heat, latticed filament


602


disperses or “flashes” the getter material coated thereon throughout the interior surface of auxiliary chamber


408


. However, in the present embodiment, latticed filament


602


is adapted to be exposed to an electrical current to achieve the desired heating. To insure proper passage of current throughout its entire length, the various rows and columns of latticed filament


602


must not contact each other at respective intersections thereof. Many of the numerous substantial benefits described in conjunction with the embodiment of

FIG. 6A

apply to the present embodiment as well.





FIGS. 6C and 6D

are schematic representations of getter material disposed on a plurality of separately bundled filaments


604




a


,


604




b


,


606




a


and


606




b


, in accordance with another embodiment of the present claimed invention. In these embodiments, multiple bundles or lattices of getter coated filaments are disposed within auxiliary chamber


408


. In so doing, the distinctly partitioned filaments can be separately activated. For example, a first filament (e.g.


604




a


or


606




a


) can be activated at the factory, and a second filament (e.g.


604




b


or


606




b


) can later be activated in situ. As a result, the getter material is refreshable when desired by the customer. Although specific combination of filaments are shown in

FIGS. 6C and 6D

, the present invention is well suited to using a greater number of filaments in a given auxiliary chamber, and the present invention is also well suited to having a combination including both bundled and latticed filaments in the same auxiliary chamber.




With reference to

FIG. 4

, auxiliary chamber


408


of the present embodiment does not have tubulation extending therefrom. That is, auxiliary chamber


408


is, for example, attached to display device


400


in a vacuum environment. In such an embodiment, it may not be necessary to perform any additional evacuating processes. Thus, the present invention is well suited to an embodiment in which auxiliary device


408


does not include tubulation.




Referring now to

FIG. 7

, another embodiment of the present invention is shown. In this embodiment, auxiliary chamber


408


of

FIG. 4

includes tubulation


700


. Unlike conventional devices which attach tubulation directly to the active environment of the display device, tubulation


700


of the present embodiment is attached to auxiliary chamber


40


. Tubulation


700


is used during a pump-out process to evacuate the active environment of display device


400


and auxiliary chamber


408


. More specifically, the end


702


of tubulation


700


is coupled to a vacuum source, not shown. The vacuum source evacuates the interior of auxiliary chamber


408


and the active environment of display device


400


via tubulation


700


. In the present embodiment, tubulation


700


extends from auxiliary chamber


408


such that it does not extend beyond the edge of the display device


400


. More particularly, in the embodiment of

FIG. 7

, tubulation


700


projects “inwardly” (i.e. towards the central portion of display device


400


) as opposed to projecting outwardly (i.e. directly towards a border of display device


400


). Thus, unlike conventional tubulation configurations (see e.g. tubulation


118


of Prior Art FIG.


3


), tubulation


700


of the present embodiment does not interfere with, for example, sealing processes used to secure cathode


402


and faceplate


404


together. Additionally, unlike conventional tubulation configurations (see e.g. tubulation


114


of Prior Art FIG.


2


), tubulation


700


maintains a low profile and, thus, does not significantly alter or increase the “envelope” of display device


400


. Hence, low profile, inwardly projecting tubulation


700


does not restrict or limit the locations and environments in which display device


400


can be used. The present invention is also suited to embodiments in which tubulation


700


projects other than towards the central portion of display device


400


.




Referring still to

FIG. 7

, in the present embodiment, tubulation


700


is comprised of metal. More particularly, in the embodiment of

FIG. 7

, tubulation


700


is comprised of a soft metal such as, for example, nickel, copper, aluminum, and the like. Although such soft metals are recited in the present embodiment, the present invention is also well suited to the use of various other types of metals. Likewise, the present embodiment is also well. suited to forming tubulation


700


of glass, ceramic, or various other non-metal materials.




With reference still to

FIG. 7

, several substantial advantages are achieved by forming tubulation


700


of metal. For example, metal tubulation


700


is generally stronger than glass tubulation. This increased strength improves the robustness of the manufacturing process and leads to improved yield. Also, metal tubulation is more easily manufactured and coupled to auxiliary chamber


408


. For example, when auxiliary chamber


408


is formed of metal, if tubulation


700


is also formed of metal, a welding process can reliably secure tubulation


700


to auxiliary chamber


408


. The present invention is also well suited to securing metal tubulation to a metal or non-metal auxiliary chamber using various other bonding procedures. For example, in an embodiment in which auxiliary chamber


408


is comprised of ceramic material and tubulation


700


is comprised of metal, tubulation


700


is well suited to being, for example, frit-sealed or brazed to ceramic auxiliary chamber


408


.




Referring now to

FIG. 8

, another advantage associated with forming tubulation


700


from metal is shown. In the embodiment of

FIG. 8

, tubulation


700


is comprised of a bendable metal. As a result, tubulation


700


is bent to facilitate coupling of end


702


of tubulation


700


to a vacuum source. Thus, despite the location and orientation of auxiliary chamber


408


tubulation


700


can be bent or configured to provide ready access for a vacuum source or other device to end


702


of tubulation


700


. Furthermore, after the evacuation process, tubulation


700


can be bent to the position shown in FIG.


7


. In so doing, the present embodiment maintains its low profile and, thus, does not significantly alter or increase the “envelope” of display device


400


. Additionally, tubulation


700


of the present embodiment can be configured to extend beyond the edge of display device


400


to facilitate easy access to a vacuum source. However, prior to the evacuation process, tubulation


700


can be bent to ensure that tubulation


700


does not interfere with, for example, a laser sealing process. In an embodiment in which tubulation


700


is formed of glass, the glass tubulation is heated and is then bent to a desired shape.




With reference next to

FIG. 9

, another embodiment of the present invention is shown in which tubulation


700


extending from auxiliary chamber


408


has a sealed end


900


. Typically, after a final evacuation process, the present embodiment seals tubulation


700


forming sealed end


900


. In so doing, an evacuated environment is maintained within auxiliary chamber


408


and the active environment of display device


400


. In the embodiments of the present invention, sealed end


900


is achieved in any of numerous ways. In an embodiment in which tubulation


700


is comprised of glass, a heating process is used to obtain sealed end


900


. When tubulation


700


is comprised of metal, the present embodiment forms sealed end


900


using a non-thermal sealing process. Such a non-thermal process includes, for example, a mechanical pinching process, and the like. By using such a non-thermal sealing process, the present embodiment does not subject components of display device


400


and/or auxiliary chamber


408


to a deleterious thermal load or thermal shock. Additionally, such a mechanical sealing process results in minimal residual tubulation extending from auxiliary chamber


408


.




With reference now to

FIG. 10

, auxiliary chamber


408


of the present embodiment does not have tubulation extending therefrom. Instead, auxiliary chamber


408


is sealed using a plug seal


1000


. In such an embodiment, a plug of, for example, molten quartz glass or indium is used to seal auxiliary chamber


408


after an evacuation process. As can be seen from the embodiment of

FIG. 10

, by using plug seal


1000


, the present embodiment maintains a low profile and, thus, does not significantly alter or increase the “envelope” of display device


400


. Additionally, a plug seal can be used at any location on auxiliary chamber


408


. Hence, low profile, plug seal


1000


does not restrict or limit the locations and environments in which display device


400


can be used.




With reference now to

FIG. 11

, a flow chart


1100


of steps used to attach auxiliary chamber


408


to cathode


402


, both of FIGS.


4


,


5


, and


7


-


10


, is shown. Certain types of sealing material such as, for example, low temperature sealing frit do not bond well to smooth surfaces. That is, in certain conditions, when using such a sealing frit, the seal or bond created between two surfaces may be more mechanical then chemical. The present embodiment provides a method for attaching one smooth surface (e.g. cathode


402


or other surface of display device


400


) and another smooth surface (e.g. the bottom surface of auxiliary chamber


408


) together. As shown at step


1102


, the present embodiment first conditions a surface of display device


400


such that a conditioned surface of display device


400


is generated. In the present embodiment, the surface of display device


400


is the top surface of cathode


402


of display device


400


. In so doing, the conditioned surface of display device


400


is then adapted to have auxiliary chamber


408


bonded thereto. An embodiment of the process of step


1102


will be described in detail below in conjunction with the discussion of FIG.


12


.




At step


1104


, the present embodiment conditions a surface of auxiliary chamber


408


such that a conditioned surface of auxiliary chamber


408


is generated. In the present embodiment, the conditioned surface of auxiliary chamber


408


is the bottom surface of auxiliary chamber


408


. In so doing, the conditioned surface of auxiliary chamber


408


is then adapted to be bonded to the conditioned surface of display device


400


. An embodiment of the process of step


1104


will be described in detail below in conjunction with the discussion of FIG.


13


.




Next, at step


1106


, the present embodiment bonds the conditioned surface of auxiliary chamber


408


to the conditioned surface of display device


400


. This, bonding step can occur, for example, in a vacuum such that no tubulation need be attached to auxiliary chamber


408


. However, the present embodiment is also well suited to bonding auxiliary chamber


408


to cathode


402


in a non-vacuum environment and then evacuating auxiliary chamber


408


and the active environment of display device


400


using tubulation coupled to auxiliary chamber


408


. An embodiment of the process of step


1106


will be described in detail below in conjunction with the discussion of FIG.


14


. Additionally, the present invention is also well suited to an embodiment in which only the surface of display device


400


is conditioned, or only the surface of auxiliary chamber


408


is conditioned.




With reference now to

FIG. 12

, a flow chart


1200


of steps performed during conditioning of a surface of display device


400


is shown. As recited at step


1202


, the present embodiment applies frit to the surface of display device


400


. More particularly, at step


1202


, the present embodiment applies frit without binders to the surface of display device


400


. As a result, the frit can be preglazed in vacuum, not in air, so that the active elements of display device will not oxidize and are not deleteriously exposed to any binders. In one embodiment, the frit is suspended in isopropyl alcohol (IPA). The IPA containing frit therein is then, for example, “painted” onto the surface of display device


400


at the desired location.




Next, at step


1204


, the surface of display device


400


is subjected to a heating step to expedite evaporation of the IPA. The evaporation of the IPA leaves a frit coating on the surface of display device


400


. This heating occurs in a vacuum oven or inert atmosphere at high temperatures. In so doing, the sensitive active elements of display device


400


are not deleteriously exposed to any binders, and the active elements of display device


400


are not deleteriously exposed to an unwanted oxygen atmosphere.




With reference now to

FIG. 13

, a flow chart


1300


of steps performed during conditioning of a surface of auxiliary chamber


408


is shown. As recited at step


1302


, the present embodiment applies frit to the surface of auxiliary chamber


408


. More particularly, in the present embodiment, the frit material is applied to the bottom surface of auxiliary chamber


408


where auxiliary chamber


408


will contact display device


400


.




Next, at step


1304


, the present embodiment preglazes the frit to the bottom surface of auxiliary chamber


408


by heating auxiliary chamber


408


such that the frit is coupled to the bottom surface thereof.




With reference now to

FIG. 14

, a flow chart


1400


of steps performed during bonding of the conditioned surface of display device


400


and the conditioned surface of auxiliary chamber


408


is shown. As recited at step


1402


, the present embodiment places the conditioned surface of display device


400


and the conditioned surface of auxiliary chamber


408


in contact with each other.




Next, at step


1404


, the present embodiment exposes the conditioned surface of display device


400


and the conditioned surface of auxiliary chamber


408


to a heat source such that the conditioned surface of display device


400


and the conditioned surface of auxiliary chamber


408


are bonded together. In the present embodiment, the conditioned surface of display device


400


and the conditioned surface of auxiliary chamber


408


are exposed to a laser heating source. Although such heating is recited in the present embodiment, the present invention is also well suited to exposing the conditioned surface of display device


400


and the conditioned surface of auxiliary chamber


408


to various other heating methods such as, for example, radio frequency (RF) heating, oven heating, and the like. Additionally, in one embodiment, the conditioned surface of display device


400


and the conditioned surface of auxiliary chamber


408


are exposed to the heat source in an inert environment such that the heat does not damage active elements of display device


400


. In an embodiment in which a laser is used to bond display device


400


and auxiliary chamber


408


together, such bonding can be accomplished without requiring the use of a low temperature frit suspended in IPA.




With reference now to

FIG. 15

, a flow chart


1500


of steps performed during another embodiment of the present invention is shown. In this embodiment of the present invention, the surface of display device


400


and the surface of auxiliary chamber


408


are conditioned by a roughening process. As recited in step


1502


, the surface of display device


400


is roughened using for example, a chemical process, a mechanical process, a laser process, and the like. This process is used to create topography on the surface of display device


400


wherein the topography facilitates a bonding process. In the present embodiment, the chemical roughening process includes, for example, exposing the surface of display device


400


to an acid etch process. The mechanical roughening process includes, for example, sandblasting or sanding the surface of display device


400


. The laser roughening process includes, for example, exposing the surface of display device


400


to a laser to mark or pit the surface thereof.




At step


1504


, the surface of auxiliary chamber


408


is roughened using for example, a chemical process, a mechanical process, a laser process, and the like. This process is used to create topography on the surface of auxiliary chamber


408


wherein the topography facilitates a. bonding process. In the present embodiment, the chemical roughening process includes, for example, exposing the surface of auxiliary chamber


408


to an acid etch process. The mechanical roughening process includes, for example, sandblasting or sanding the surface of auxiliary chamber


408


. The laser roughening process includes, for example, exposing the surface of auxiliary chamber


408


to a laser to mark or pit the surface thereof.




At step


1506


, the present embodiment uses an adhesive to bond the roughened surface of display device


400


and the roughened surface of auxiliary chamber


408


together. The present embodiment is well suited to using any of various types of adhesive to accomplish step


1506


. Additionally, the present invention is also well suited to an embodiment in which only the surface of display device


400


is roughened, or only the surface of auxiliary chamber


408


is roughened. Furthermore, the present invention is also well suited to an embodiment in which the surface of display device


400


is conditioned with frit, and the surface of auxiliary chamber


408


is roughened as described above, or surface of display device


400


is roughened as described above, and the surface of auxiliary chamber


408


is conditioned with frit.




With reference now to

FIG. 16A

, another embodiment of the present invention is shown in which an auxiliary chamber


408


′ has a variable volume. More specifically, in the present embodiment auxiliary chamber


408


′ has an expandable portion


1600


. In

FIG. 16A

, expandable portion


1600


is in a compressed state. In the present embodiment, expandable portion is comprised of a bellow-like structure, which is maintained in the compressed state during evacuation and sealing (i.e. tip-off) of display


400


. As a result, the present embodiment maintains a low profile as described above in detail.




Referring now to

FIG. 16B

, auxiliary chamber


408


′ is shown in an expanded state. As a result, the volume of auxiliary chamber has been increased. Thus, the present embodiment provides an auxiliary chamber having a variable volume. In operation, the present embodiment is extended after evacuation and sealing (i.e. tip-off) of display


400


to increase the volume of auxiliary chamber


408


′. Getter


410


is then activated (e.g. flashed), and then auxiliary chamber


408


′ is returned to its compressed state to return display


400


to the desired low profile. In this embodiment, the surface of the getter will be deposited (flashed), giving improved dispersion of the getter material, and, in the end, maintaining the desired low-profile.




With reference to

FIGS. 17A-17C

, an embodiment of the present invention is shown in which auxiliary chamber


170


includes cylindrical housing


171


. In one embodiment, cylindrical housing


171


is formed of steel. However, the present invention is well suited to the use of various other types of metals. The present invention is also well suited to the use of a low expansion alloy that is close to the coefficient of thermal expansion of the display glass.




In the embodiment shown in

FIGS. 17B-17C

, a getter is formed of a spiral of Non-Evaporable Getter (NEG) material


173


. Conductive element


174


is disposed centrally within each cylindrical housing


171


and extends through insulator


175


that forms a hermetic seal between cylindrical housing


171


and conductive element


174


. Conductive element


174


connects electrically to one end of NEG material


173


. The other end of NEG material


173


is electrically connected to cylindrical housing


171


. Passing a current through conductive element


174


, and through NEG material


173


, and out through cylindrical housing


171


, heats NEG material


173


for activation of NEG material


173


.




In the embodiment shown in

FIG. 17D

a row of auxiliary chambers


170


are attached to display glass


172


. Openings (not shown) extend through display glass


172


below each of auxiliary chambers


170


. In one embodiment, each of auxiliary chambers


170


are attached to display glass


172


using a metal solder, solder glass or other adhesive by heating or friction welding. However, the present invention is well suited to the use of other methods for attaching auxiliary chambers


170


to display glass


172


.




Referring to

FIG. 17D

, in one embodiment, power source


177


is electrically coupled to cylindrical housings


171


and to conductive elements


174


by conductive wire


176


. Upon the application of power, NEG material


173


within each cylindrical housing


171


is activated. Though the embodiment shown in

FIG. 17D

is wired in series, the present invention is well suited to an embodiment in which each of cylindrical housings


171


and conductive elements


174


are wired in parallel to power source


177


. In an embodiment in which each of cylindrical housings


171


are wired in parallel to power source


177


, cylindrical housings


171


can be individually activated.




Referring still to

FIG. 17D

, in one embodiment, each cylindrical housing


171


has a reduced height. In one specific embodiment, each cylindrical housing has a height of approximately 0.5 centimeters and a diameter of approximately 1 centimeter. In this embodiment, more than 500 square millimeters of 0.4 millimeter thick NEG material is disposed within cylindrical housing


171


. Because cylindrical housing


171


is made of metal and has a small size relative to prior art devices, the present invention is less likely to adversely affect mechanical properties (e.g. compliance, seal strength, etc.) than prior art large glass auxiliary compartments.




The embodiments shown in

FIGS. 17A-17D

allow for periodic activation by current heating during various stages of conditioning. In addition, the embodiments shown in

FIGS. 17A-17D

can be reactivated throughout the life of the display. Thus, for example, NEG material


173


can be reactivated at intervals during the consumer life of the display. For example, NEG material


173


can be reactivated during battery charging operations, during initial power-up of the display, etc. This would extend the lifetime of the display by periodically improving vacuum and compensating for the long-term vacuum degradation associated with outgassing and seal permeability.




In one alternate embodiment that is shown in

FIG. 17E

, tubulation


178


extends from cylindrical housing


171


. In one embodiment, tubulation


178


is a crimpable pump port for evacuation of auxiliary chamber


170


and the display device to which auxiliary chamber


170


is attached.




In yet another embodiment that is shown in

FIG. 17F

, high voltage (anode) feed-through is provided by conductive cable


191


that extends through opening


193


in display glass


172


. In one embodiment, spring-loaded contact


192


is attached to conductive cable


191


.




Referring now to

FIG. 18

, an embodiment is shown that includes barium flash bulb


181


that is disposed within auxiliary chamber


180


. In the present embodiment, barium flash bulb


181


includes barium material that is disposed on filament


183


. In one embodiment, filament


183


is a bundled filament such as bundled filament


600


of FIG.


6


A. Alternatively, filament


183


is arranged in a lattice configuration to produce a “latticed filament” such as lattice filament


602


of FIG.


6


B. In the present embodiment, filament


183


is comprised of tungsten. However, the present embodiment is also well suited to the use of various other filament materials, such as, for example, titanium, tantalum, tungsten, a tantalum-titanium alloy, and the like.




Still referring to

FIG. 18

, in one embodiment, auxiliary chamber


180


includes a sieve-like bottom plate


187


that includes openings


182


extending therethrough. Openings


182


allow contaminant particles to move into auxiliary chamber


180


. In one embodiment, bottom plate


187


is coated with frit prior to assembly to housing


188


. Once auxiliary chamber


180


is assembled, filament


183


is retained within auxiliary chamber


180


. This provides for easy installation of auxiliary chamber


180


to a display device because filament


183


is retained within auxiliary chamber


180


during transport and during the attachment of auxiliary chamber


180


to the display glass.




Continuing with

FIG. 18

, electrical feed-through


184


and electrical feed-through


185


are electrically coupled to filament


183


. In one embodiment, electrical feed-through


184


and electrical feed-through


185


are fritted to auxiliary chamber


180


. Alternatively, electrical feed-throughs


184


-


185


are brazed to auxiliary chamber


180


. In one embodiment, auxiliary chamber


180


is ceramic or glass. Alternatively, auxiliary chamber


180


is metal that is coated with an insulating material such as, for example, ceramic.




In one embodiment, activation is accomplished by applying 6-12 volts of direct current to electrical feed-throughs


184


-


185


. When electrical current is applied to electrical feed-throughs


184


-


185


, filament


183


disperses or “flashes” the barium material coated thereon throughout the interior surface of auxiliary chamber


180


.




Though a single flash bulb is shown in the embodiment of

FIG. 18

, the present invention is also well suited to an embodiment in which the filament is partitioned into two or more smaller flash bulbs. The use of two flash bulbs allows for operation of one flash bulb during assembly and allows for operation of the second flash bulb by the customer. Several substantial advantages are realized by the present embodiment, many of which are discussed with reference to the embodiments of

FIGS. 4-6D

.




It has been found that flashing of barium getters produces gasses that can be deleterious to the active areas of the display. In the present embodiment, the barium getter is activated during the evacuation of the display. This evacuates gasses produced by the barium getter, eliminating the deleterious effects of the gasses produced by activation of the barium getter. Referring to

FIG. 19

, a flat panel display


200


is shown that includes backplate


201


, faceplate


202


, perimeter seal


203


, vacuum gap


204


and auxiliary compartment


205


. Openings


206


extend through backplate


201


. High emissivity surface


209


allows for heat to be conducted away from low emissivity surface


208


. In one specific embodiment, high emissivity surface


209


is a glass surface that is uncoated and low emissivity surface


208


is a glass surface that is coated with metal film


210


.




Continuing with

FIG. 19

, getter


207


is disposed within auxiliary compartment


205


such that, upon activation, getter


207


deposits a film of getter material over low emissivity surface


208


. The heat generated by flashing getter


207


is conducted out of the back of auxiliary compartment


205


as shown by arrow


211


. This minimizes the temperature increase of low emissivity surface


208


.





FIG. 20

shows an embodiment in which low emissivity surface


208


′ is located in the border region surrounding the active area of the display. Upon activation of getter


207


, a film of getter material is deposited over low emissivity surface


208


′. The heat generated by flashing getter


207


is conducted out of the display and away from low emissivity surface


208


′ through high emissivity surface


209


′.




Referring to

FIGS. 19-20

, in one embodiment, getter


207


is a barium getter. Because the heat generated by flashing getter


207


is conducted out of the display and away from low emissivity surface


208


, low emissivity surface


208


remains relatively cool. Because the surface onto which the barium film is to be deposited is relatively cool, the resulting barium film is porous and has good gettering properties.





FIGS. 21A-21B

, show an embodiment in which display device


214


and display device


214


′ include a large surface area structure


212


. In the present embodiment, large surface area structure


212


is a carbon felt structure that is disposed near getter


207


. In the present embodiment, getter


207


is a barium getter. Carbon felt structure


212


can be disposed in an auxiliary compartment


205


as is shown in

FIG. 21A

or can be disposed in the border region surrounding the active area of the display as shown by FIG.


21


B. When getter


207


is flashed, a film of getter material is deposited on carbon felt structure


212


. The carbon felt structure


212


provides a large surface area and is a high temperature, vacuum compatible material. Thus, the resulting film of getter material has a high surface area and good gettering ability. The use of carbon felt is particularly advantageous in the embodiment shown in

FIG. 21B

because the amount of space in the border region is limited.





FIG. 22

shows a support


220


that includes extending members


221


extending from each side of support


220


near each end of support


220


. In the present embodiment, support


220


is formed of wire that is spot welded. Extending members


221


are adapted to be pinched towards the body


222


of support


220


such that support


220


can be easily inserted into an auxiliary chamber


223


. Once support


220


is properly positioned in auxiliary chamber


223


, extending members


221


are allowed to expand such that they contact the side surfaces of auxiliary chamber


223


. The tension provided by extending members


221


holds support


220


securely in place. Getters


224


are attached to support


220


such that getters


224


are suspended within auxiliary chamber


223


. In one embodiment, getters


224


are barium getters. However, the present invention is well suited for use with getters


224


that are formed of other materials.




Referring still to

FIG. 22

, by suspending getters


224


within auxiliary chamber


223


, getters


224


are isolated from tube and auxiliary compartment glass. The use of support


22


eliminates the need for using adhesive to attach a getter. The adhesive that is commonly used in the prior art for attaching a getter outgasses. Thus, the present invention eliminates outgassing associated with adhesive as commonly occurs in prior art getter assemblies. In addition, the time consuming adhesive cure operations of prior art getter assemblies is avoided by use of the present invention.




A non-evaporable getter (NEG) has a surface capacity that is much lower as compared to the bulk capacity of the NEG. The present invention provides for reactivation of the NEG once surface saturation occurs. By reactivating the NEG, the absorbed gasses are diffused into the bulk of the NEG, restoring the NEG's room temperature surface capacity. By reactivation of the NEG multiple times, the bulk capacity of the NEG is fully utilized.




In one embodiment, reactivation is performed by heating the NEG to a high temperature for a predetermined time period. The present embodiment uses a laser for reactivation. However, the present invention is well suited for use of other heating methods. In one embodiment, a single pass of a laser over the whole area of the getter is performed so as to heat the NEG to a temperature of approximately 900 degrees Centigrade for approximately 20 seconds. In one embodiment, the NEG is reactivated in intervals during the display burn-in and the initial life of the display, when outgassing level of the display components is still high. This reactivation can continue for the life of the display.




Referring now to

FIG. 23A

, pre-flashed getter capsule


230


includes housing


231


within which support structures


232


extend. In one embodiment, support structures


232


are ribs. Alternatively, support structures


232


are posts. Cover


233


attaches to housing


231


so as to form an enclosure therebetween. In one embodiment, cover


223


is a thin metal plate. Within the enclosure, pre-flashed getter material


235


is a film that extends over the interior surfaces of housing


231


and extends over support structures


232


. In one embodiment, housing


231


and support structures


232


are formed of metal. However, the present invention is well suited for use of a housing


231


, support structures


232


and cover


233


that are formed of other materials such as, for example, glass. Thin plug


234


is formed within cover


233


and is adapted to be broken, melted or otherwise removed so as to expose the interior of pre-flashed getter capsule


230


. However, the present invention is well suited for use of a cover that does not include a thin plug and which is adapted to be broken, melted or otherwise removed so as to expose the interior of pre-flashed getter capsule


230


.




The pre-flashed getter capsule


230


of

FIG. 23A

can be formed by flashing a barium getter onto the inside of the housing


231


in a vacuum chamber. Preferably, the barium getter is flashed from a long distance. Cover


233


is then placed over housing


231


and is sealed to housing


231


. The completed pre-flashed getter capsule is then removed from the vacuum chamber and is placed in an auxiliary chamber (not shown). Alternatively, the pre-flashed getter capsule


230


is placed in the border region surrounding the active areas of a display device.




Continuing with

FIG. 23A

, pre-flashed getter capsule


230


is activated by breaking, melting or otherwise removing thin plug


234


so as to expose the interior of pre-flashed getter capsule


230


. In one embodiment the thin plug


234


is a low temperature plug that is broken by laser heating or radio frequency energy. The present invention is also well adapted for using a thin plug


234


that has metal antennas on it or that is coupled to a high thermal expansion piece of metal, crush-chambers, or by using a magnet to move an internal steel ball.





FIG. 23B

shows an embodiment in which a pre-flashed getter capsule


236


is formed within auxiliary chamber


237


. Optionally, tubulation


229


is also disposed in auxiliary chamber


237


. In the present embodiment, support structures


232


are formed within auxiliary chamber


237


. Pre-flashed getter material


235


is disposed over the inner surface of auxiliary chamber


237


below ledge


238


such that pre-flashed getter material


235


overlies the interior surfaces of auxiliary chamber


237


and support structures


232


. Cover


239


rests on ledge


238


so as to form a sealed enclosure. In the present embodiment, cover


239


is seal glass having a thickness of approximately 2 mils. However, the present invention is well suited for the use of covers formed of other materials. Also, the present invention is well suited for the use of thin plugs disposed within cover


239


.




Continuing with

FIG. 23B

, though any of a number of different methods can be used for sealing cover


239


to auxiliary chamber


237


, in the present embodiment, a glass frit seal is used. Support structures


232


can be posts


232


′ as shown in

FIG. 23C

or ribs


232


″ as shown in FIG.


23


D. However, the present invention is also well suited to other shapes of support structure.




Referring still to

FIG. 23B

, activation is accomplished by breaking, melting or otherwise forming openings within cover


239


. This exposes pre-flashed getter material


235


. By flashing a getter in a vacuum environment, the flashing operation can be conducted under optimal conditions. This results in good quality pre-flashed getter material


235


that has good gettering abilities.




Referring now to

FIG. 24

, an assembly


240


is shown that includes a lower Radio Frequency (RF) coil


241


, an upper RF coil


242


and getters


243


-


244


that are disposed in auxiliary chamber


205


. Alternatively, assembly


240


can be located within the border region of a display device or RF coils


241


-


242


can be placed outside of the auxiliary chamber. In one embodiment, RF coil


241


and RF coil


242


are phased array antennas that are positioned and phased such that, when lower RF coil


241


and upper RF coil


242


are energized, areas of constructive interference and areas of destructive interference result.




In one embodiment, getter


243


is in an area of constructive interference and getter


244


is in an area of destructive interference. This allows for the selective activation of getter


243


by generating RF radiation through upper RF coil


241


and lower RF coil


243


. The remaining getter


244


can then be activated at a later time. In one embodiment, getter


243


is a barium getter and getter


244


is comprised of NEG material. This allows for selectively activating the barium getter


243


without activating the getter


244


. In one embodiment, a laser or other heating means is used to activate getter


244


at a later time.





FIG. 25

shows an embodiment that includes Non-Evaporable getters


251


and


252


that are disposed inside of display


250


. Both getter


251


and getter


252


are coupled to a power source (not shown) such that getter


251


and getter


252


can be selectively activated. In one embodiment, getter


251


is activated immediately prior to sealing the display, while the display is still hot and the components of the display have a high outgassing rate. Getter


251


remains at activation temperature (e.g. 500 degrees Centigrade) until the other parts of the display are cooled down to room temperature. This provides the maximum capacity for absorption of CO, CO


2


and H


2


O. Referring still to

FIG. 25

, getter


252


can be activated later when the display is still in the factory. In one embodiment, getter


252


is activated by applying heat so as to heat getter


252


to a temperature of approximately 500 degrees Centigrade for approximately 10 minutes. The activation of getter


252


provides the necessary pressure inside the display over the lifetime of the display.




Referring now to

FIG. 26A

, a planar evaporable getter


260


is shown that includes nickel foil layer


261


over which barium aluminum (BaAl


4


) material


262


is disposed. Nickel foil layer


263


is disposed over barium aluminum layer


262


.




Referring now to

FIG. 26B

, an embodiment of a planar evaporable getter


260


′ is shown that includes formed nickel substrate


264


. In the present embodiment, nickel substrate


264


is formed so as to produce a number of parallel channels within nickel substrate


264


. Barium aluminum (BaAl


4


) material


262


is disposed within each channel. Nickel film


265


is disposed such that it overlies barium aluminum material


262


.




In the embodiment shown in

FIG. 26C

, planar evaporable getter


260


″ includes nickel substrate


264


′ that has circular cavities. Barium aluminum material


262


is disposed within each circular cavity. Nickel film


265


′ overlies barium aluminum material


262


. Though cavities are shown to be circular cavities, the present invention is well adapted for use of other shapes such as, for example, rectangular shapes, triangular shapes, etc.




In one embodiment, nickel substrate


264


and nickel substrate


264


′ are formed by pressing, electroforming, or otherwise shaping a nickel sheet. Barium aluminum material


262


is then deposited using a powder deposition process or by pressing barium aluminum material


262


into the sheet and wiping the surface with a doctor blade. In one embodiment, the cavities shown in

FIGS. 26A-26C

are in the range of 0.001 to 0.010 inches in width and 0.001 to 0.010 inches deep.




In the embodiment shown in

FIG. 26D

, a planar evaporable getter


260


is placed in a flat panel display


270


. In the present embodiment, planar evaporable getter


260


of

FIG. 26A

, planar evaporable getter


260


′ of

FIG. 26B

or planar evaporable getter


260


″ of

FIG. 26C

is used. Upon optical irradiation (laser or infrared radiation) of planar evaporable getter


260


, barium aluminum material


262


is flashed, forming a film of barium material


267


. The exothermic reaction is BaAl


4


+4Ni→Ba+4NiAl. In addition, the present invention is well adapted for using materials other than barium such as, for example, lithium.




In the embodiment shown in

FIG. 26E

, two planar evaporable getters


260


are disposed opposite each other within flat panel display


270


′. In the present embodiment, planar evaporable getter


260


of

FIG. 26A

, planar evaporable getter


260


′ of

FIG. 26B

or planar evaporable getter


260


″ of

FIG. 26C

is used. In the present embodiment, both planar evaporable getters


260


are activated at the same time, producing a film of barium material


268


. By using two planar evaporable getters


260


that are located opposite each other, the resulting a film of barium material


268


is twice the size of film of barium material


267


of FIG.


26


D.




The embodiments shown in

FIGS. 26B and 26C

allow for the sequential heating (flashing) of deposits of barium aluminum material


262


. By sequentially heating deposits of barium aluminum material


262


, a low deposition rate is obtained. This allows for the formation of renewable thin films of barium material


267


and


268


. By sequentially heating the individual deposits of barium aluminum material


262


, a thin film is incrementally deposited at a low deposition rate. This minimizes heating of the existing thin film (sintering) and prevents the associated reduced sorption capacity.




Referring still to

FIGS. 26A-26E

, in one embodiment, deposits of barium aluminum material


262


are sequentially activated during the initial life of the display to compensate for variable levels of outgassing during turn-on of the device. When used in conjunction with optional NEG


269


, the optional NEG


269


can be routinely activated during the initial outgassing of the display components and the planar evaporable getter could be flashed to provide a very high capacity pumping at the time the display is shipped to the customer.




Thus, the present invention provides an apparatus that removes contaminants from a display device without compromising the usable amount of space available within the display device. The present invention also provides an auxiliary chamber that realizes the above listed accomplishment and which does not deleteriously expose features of the display device to getter material. The present invention further provides an auxiliary chamber which achieves the above-listed accomplishments but which does not significantly increase or alter the overall dimensions of the display device. The present invention also provides an apparatus with improved particle removal.




The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.



Claims
  • 1. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber, wherein said auxiliary chamber comprises metal, and is adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; and a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber.
  • 2. The apparatus of claim 1 for removing contaminants from a display device wherein said auxiliary chamber includes a cylindrical housing.
  • 3. The apparatus of claim 2 for removing contaminants from a display device wherein said getter is non evaporable getter material.
  • 4. The apparatus of claim 3 for removing contaminants from a display device wherein said getter includes a spiral of non evaporable getter material.
  • 5. The apparatus of claim 2 for removing contaminants from a display device further including:a conductive element disposed centrally within said cylindrical housing.
  • 6. The apparatus of claim 1 for removing contaminants from a display device further including:a power source coupled to said conductive element and coupled to said cylindrical housing, said power source adapted to provide electrical current for activating said getter.
  • 7. The apparatus of claim 6 for removing contaminants from a display device further including:tubulation coupled to said cylindrical housing, said tubulation adapted to be coupled to a vacuum source during evacuation of said cylindrical housing.
  • 8. The apparatus of claim 7 for removing contaminants from a display device wherein said tubulation comprises a crimpable pump port.
  • 9. The apparatus of claim 6 for removing contaminants from a display device wherein said auxiliary chamber is further adapted to be disposed above at least one hole extending through said surface of said display device such that said contaminants within said display device can travel from said display device through said holes and into said auxiliary chamber.
  • 10. The apparatus of claim 1 for removing contaminants from a display device further including:a high voltage feed-through; and a spring loaded contact coupled to said high voltage feed-through.
  • 11. The apparatus of claim 1 for removing contaminants from a display device wherein said getter is disposed on a filament.
  • 12. The apparatus of claim 11 for removing contaminants from a display device wherein said filament is configured in a lattice arrangement.
  • 13. The apparatus of claim 11 for removing contaminants from a display device wherein said filament is configured in a bundled arrangement.
  • 14. The apparatus of claim 1 for removing contaminants from a display device wherein said getter is disposed on a plurality of separate filaments located within said auxiliary chamber.
  • 15. The apparatus of claim 1 for removing contaminants from a display device wherein said getter is evaporable getter.
  • 16. The apparatus of claim 15 for removing contaminants from a display device wherein said evaporable getter includes barium.
  • 17. The apparatus of claim 12 for removing contaminants from a display device wherein said getter comprises barium coated on said filament.
  • 18. The apparatus of claim 17 for removing contaminants from a display device wherein said auxiliary chamber further comprises:a bottom plate having openings disposed therethrough; a housing disposed over said bottom plate so as to form an enclosure therebetween; a first electrical feed-through extending through said housing and electrically coupled to said filament; and a second electrical feed-through extending through said housing and electrically coupled to said filament.
  • 19. The apparatus of claim 18 for removing contaminants from a display device further comprising:frit disposed on said bottom plate, said frit adapted to couple said auxiliary chamber to said surface of said display device.
  • 20. The apparatus of claim 1 for removing contaminants from a display device further comprising:a metal film selectively deposited within said auxiliary chamber, said metal film adapted to receive getter material upon activation of said getter.
  • 21. The apparatus of claim 1 for removing contaminants from a display device further comprising:a carbon felt structure adapted to receive getter material upon activation of said getter.
  • 22. The apparatus of claim 1 for removing contaminants from a display device wherein said auxiliary chamber includes a plurality of side surfaces, said apparatus further comprising:a support coupled to said getter, said support having a plurality of extending members extending therefrom, said plurality of extending members adapted to engage ones of said plurality of side surfaces of said auxiliary chamber such that said getter is suspended within said auxiliary chamber.
  • 23. The apparatus of claim 1 for removing contaminants from a display device wherein said getter comprises non evaporative getter material, said getter activated for absorbing gasses and subsequently reactivated such that said absorbed gasses are diffused into said getter.
  • 24. The apparatus of claim 1 for removing contaminants from a display device further comprising:a housing; a cover extending over said housing, said housing and said cover forming a sealed enclosure therebetween; and wherein said getter includes pre-flashed getter material disposed within said sealed enclosure.
  • 25. The apparatus of claim 24 for removing contaminants from a display device further comprising:a low temperature plug disposed in said cover and adapted to be melted.
  • 26. The apparatus of claim 24 for removing contaminants from a display device further comprising:a plug disposed in said cover, said plug having a plurality of antennas coupled thereto.
  • 27. The apparatus of claim 24 for removing contaminants from a display device further comprising:a plug disposed in said cover, said plug having a high thermal expansion piece of metal coupled thereto.
  • 28. The apparatus of claim 24 for removing contaminants wherein said pre-flashed getter material comprises barium.
  • 29. The apparatus of claim 1 for removing contaminants further comprising:a cover disposed over a portion of said auxiliary chamber so as to form a sealed enclosure therewithin; and wherein said getter includes pre-flashed getter material disposed within said sealed enclosure.
  • 30. The apparatus of claim 29 for removing contaminants wherein said pre-flashed getter material comprises barium.
  • 31. The apparatus of claim 29 for removing contaminants from a display device wherein said cover comprises glass.
  • 32. The apparatus of claim 29 for removing contaminants from a display device wherein said auxiliary chamber further includes a ledge adapted to receive said cover.
  • 33. The apparatus of claim 1 for removing contaminants from a display device wherein said getter further comprises a first getter and a second getter, said apparatus further comprising:a first coil disposed near said first getter and said second getter; a second coil disposed near said first getter and said second getter, said first coil and said second coil adapted to be energized so as to radiate energy therebetween for selectively activating said first getter.
  • 34. The apparatus of claim 33 for removing contaminants from a display device wherein said first getter comprises a barium getter and wherein said second getter comprises a non evaporable getter.
  • 35. The apparatus of claim 1 for removing contaminants from a display device wherein said getter comprises a first getter and a second getter, said first getter and said second getter coupled to a power source such that said first getter and said second getter can be selectively activated.
  • 36. The apparatus of claim 1 for removing contaminants from a display device wherein said getter is activated using a laser.
  • 37. The apparatus of claim 1 for removing contaminants from a display device wherein said getter further comprises:a first foil layer; a layer of barium aluminum material; and a second foil layer disposed over said barium aluminum layer.
  • 38. The apparatus of claim 1 for removing contaminants from a display device wherein said getter further comprises:a substrate having a plurality of channels formed therewithin; evaporable getter material disposed within said plurality of channels; and a film disposed over said evaporable getter material.
  • 39. The apparatus of claim 1 for removing contaminants from a display device wherein said getter further comprises:a substrate having a plurality of cavities formed therewithin; barium aluminum material disposed within said plurality of cavities; and a film disposed over said barium aluminum material.
  • 40. The apparatus of claim 39 for removing contaminants from a display device wherein said cavities are circular.
  • 41. The apparatus of claim 39 for removing contaminants from a display device wherein said cavities are rectangular.
  • 42. An apparatus for removing contaminants from a display device comprising:a housing; a cover extending over said housing, said housing and said cover forming a sealed enclosure therebetween; pre-flashed getter material disposed within said sealed enclosure; and a low temperature plug disposed within said cover and adapted to be melted.
  • 43. An apparatus for removing contaminants from a display device comprising:a housing; a cover extending over said housing, said housing and said cover forming a sealed enclosure therebetween; pre-flashed getter material disposed within said sealed enclosure; and a plug having a plurality of antennas coupled thereto.
  • 44. An apparatus for removing contaminants from a display device comprising:a housing; a cover extending over said housing, said housing and said cover forming a sealed enclosure therebetween; pre-flashed getter material disposed within said sealed enclosure; and a plug having a high thermal expansion piece of metal coupled thereto.
  • 45. The apparatus of claim 42 for removing contaminants wherein said pre-flashed getter material comprises barium.
  • 46. The apparatus of claim 42 for removing contaminants wherein said cover comprises glass.
  • 47. An apparatus for removing contaminants from a display device that includes a faceplate and a backplate that are coupled together so as to form an enclosure therebetween, said apparatus comprising:a first getter; a second getter; a first coil disposed near said first getter and said second getter; and a second coil disposed near said first getter and said second getter, said first coil and said second coil adapted to be energized so as to radiate energy therebetween for selectively activating said first getter.
  • 48. The apparatus of claim 47 for removing contaminants from a display device wherein said first getter comprises a barium getter and wherein said second getter comprises a non evaporable getter.
  • 49. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter configured in a lattice arrangement and disposed on a barium-coated filament within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; a bottom plate having openings disposed therethrough; a housing disposed over said bottom plate so as to form an enclosure therebetween; a first electrical feed-through extending through said housing and electrically coupled to said filament; and a second electrical feed-through extending through said housing and electrically coupled to said filament.
  • 50. The apparatus of claim 49 for removing contaminants from a display device further comprising:frit disposed on said bottom plate, said frit adapted to couple said auxiliary chamber to said surface of said display device.
  • 51. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; and a metal film selectively deposited within said auxiliary chamber, said metal film adapted to receive getter material upon activation of said getter.
  • 52. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; and a carbon felt structure adapted to receive getter material upon activation of said getter.
  • 53. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; a housing; a cover extending over said housing, said housing and said cover forming a sealed enclosure therebetween; wherein said getter includes pre-flashed getter material disposed within said sealed enclosure; and a low temperature plug disposed in said cover and adapted to be melted.
  • 54. The apparatus of claim 53 for removing contaminants from a display device further comprising:a plug disposed in said cover, said plug having a plurality of antennas coupled thereto.
  • 55. The apparatus of claim 53 for removing contaminants from a display device further comprising:a plug disposed in said cover, said plug having a high thermal expansion piece of metal coupled thereto.
  • 56. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; a first coil disposed near said first getter and said second getter; and a second coil disposed near said first getter and said second getter, said first coil and said second coil adapted to be energized so as to radiate energy therebetween for selectively activating said first getter.
  • 57. The apparatus of claim 56 for removing contaminants from a display device wherein said first getter comprises a barium getter and wherein said second getter comprises a non evaporable getter.
  • 58. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; and wherein said getter comprises a first getter and a second getter, said first getter and said second getter coupled to a power source such that said first getter and said second getter can be selectively activated.
  • 59. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; a first foil layer; a layer of barium aluminum material; and a second foil layer disposed over said barium aluminum layer.
  • 60. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; a substrate having a plurality of channels formed therewithin; evaporable getter material disposed within said plurality of channels; and a film disposed over said evaporable getter material.
  • 61. An apparatus for removing contaminants from a display device comprising:an auxiliary chamber adapted to be coupled to a surface of a display device such that contaminants within said display device can travel from said display device into said auxiliary chamber; a getter disposed within said auxiliary chamber, said getter adapted to capture said contaminants once said contaminants travel from said display device into said auxiliary chamber; a substrate having a plurality of cavities formed therewithin; barium aluminum material disposed within said plurality of cavities; and a film disposed over said barium aluminum material.
  • 62. The apparatus of claim 61 for removing contaminants from a display device wherein said cavities are circular.
  • 63. The apparatus of claim 61 for removing contaminants from a display device wherein said cavities are rectangular.
Parent Case Info

This application is a continuation-in-part of and claims the benefit of U.S. Non-Provisional application Ser. No. 09/196,626 filing date Nov. 18, 1998, now U.S. Pat. No. 6,147,450.

US Referenced Citations (8)
Number Name Date Kind
5514847 Makishima et al. May 1996 A
5548181 Jones Aug 1996 A
5635795 Itoh et al. Jun 1997 A
5656889 Niiyama et al. Aug 1997 A
5688708 Kato et al. Nov 1997 A
5909202 Cathey Jun 1999 A
5977706 Cho et al. Nov 1999 A
6147450 Fritz et al. Nov 2000 A
Continuation in Parts (1)
Number Date Country
Parent 09/196626 Nov 1998 US
Child 09/361334 US