1. Field of the Invention
The present invention relates to a flat lamp structure having electrodes positioned on the outer wall of a gas discharge chamber, and in particular, to a flat fluorescent lamp having electrodes disposed on different planes.
2. Description of the Related Art
As a consequence of industrial progress, developments in mobile phones, digital cameras, digital video cameras, notebook computers, and desk-top computers are now concerned with multifunctional and aesthetic design. However, the display screen used in mobile phones, digital cameras, digital video cameras, notebook computers, and desk-top computers is an essential interactive interface. The display screen provides the user with great convenience of operation. In recent years, it has become commonplace for most mobile phones, digital cameras, digital video cameras, notebook computers, and desk-top computers to employ a LCD panel as the display screen. However, the LCD panel per se is non-luminous, and a back light module must be provided at the bottom of the LCD panel to provide a light source for displaying.
The flat lamp provides excellent luminosity and uniformity and also provides a larger surface area light source. Therefore, it is widely applied as a back light source for LCD panels and for other fields of applications. The flat lamp is a plasma luminous component, essentially utilizing the electrons emitted from the cathode to collide with the inert gas between the cathode and anode within the gas discharge chamber, and the gas is ionized and excited to form plasma. After that the excited state atoms of the plasma return to the ground state by emission of UV rays, the UV rays further excite the fluorescence substance within the flat lamp, producing visible light.
Referring to
Referring again to
In the process of ignition of the flat lamp, the electrode 106 emits electrons to collide with the discharge gas 104 within the gas discharge chamber 100, and the discharge gas 104 is ionized and excited to form plasma. After that, the excited state atoms of the plasma return to the ground state by emitting UV rays, and the emitted UV rays further excite the fluorescence substance 102 within the inner wall of the gas discharge chamber 100 to produce visible light. However, on the above light luminous mechanism, the high energy ions released by the plasma generally collide through the dielectric layer, and may reach further to the electrode 106. Thus, the longevity of the flat lamp is greatly reduced.
Please note that the dielectric layer 108 covering the electrode 106 is generally fabricated by a multiple screen printing process the thickness of which is controlled between 200 μm to 250 μm. However, the fabrication process of the multiple screen printing is complicated, and the test sample capacity and yield are low. In addition, multiple screen printing can easily cause unevenness in the thickness of the film, causing each of the test samples or a single test sample with different optical characteristics of different region to differ with each other. Due to the fact that the optical characteristics of the test sample cannot be easily controlled, the designing cost for the driving circuit is increased.
Accordingly, it is an object of the present invention to provide a flat lamp structure which effectively avoids collision through the dielectric layer, improving the longevity of the flat lamp.
Another object of the present invention is to provide a flat lamp structure which effectively avoids the unevenness occurring on the dielectric substrate film due to multiple screen printing, thereby improving the luminosity and the uniformity of the flat lamp.
In order to achieve the above objects, the present invention provides a flat lamp structure comprising a gas discharge chamber; a fluorescence substance disposed on the inner wall of the gas discharge chamber; a discharge gas disposed in the gas discharge chamber; and a plurality of electrodes disposed on the outer wall of the gas discharge chamber.
The gas discharge chamber, for example, comprises a dielectric substrate; a plate disposed on the upper portion of the dielectric substrate; and a plurality of strips disposed between the dielectric substrate and the plate, and the plate connected to the edge of the dielectric substrate.
In order to achieve the above objects, the present invention provides a flat lamp structure comprising a gas discharge chamber; a fluorescence substance disposed on the inner wall of the gas discharge chamber; a discharge gas disposed in the gas discharge chamber; a plurality of electrodes disposed on the outer wall of the gas discharge chamber; and a spacer disposed on the gas discharge chamber to enhance the strength of the gas discharge chamber.
The gas discharge chamber, for example, comprises a dielectric substrate; a plate disposed on the upper portion of the dielectric substrate; and a plurality of strips disposed between the dielectric substrate and the plate, and plate connected to the edge of the dielectric substrate.
In accordance with a preferred embodiment of the present invention, the thickness of the dielectric substrate is, for example, between 0.3 mm and 1.1 mm, and the distance between the dielectric substrate and the plate, for example, is between 0.5 mm and 2.0 mm.
In accordance with the preferred embodiment of the present invention, the gas charged into the gas discharge chamber, for example, is Xe, Ne or Ar, and the electrodes, for example, include silver electrode or copper electrode.
In accordance with the preferred embodiment of the present invention, the lower portion of the dielectric substrate, for example, is stuck to a carrier substrate for carrying the gas discharge chamber containing the electrode.
In addition, an adhesive, for example, is disposed between the dielectric substrate and the carrier substrate and connects the dielectric substrate and the carrier substrate.
In accordance with the preferred embodiment of the present invention, the adhesive, for example, includes glass adhesive, UV curing adhesive or thermal curing adhesive.
In accordance with the present invention, the electrode is fabricated on the outer wall of the gas discharge chamber, and by means of the dielectric substrate as dielectric material for protecting the electrode, the uniformity with respect to thickness is good and the ability to withstand the collision of ions is excellent. Thus, the present invention does not require a dielectric layer formed by multiple screen printing covering the electrode, resulting in uniformity of luminosity and significant improvement in longevity.
Furthermore, in order to improve the longevity and efficiency of luminance, the flat fluorescent lamp of the present invention comprises at least an electrode pair formed by one first electrode and one second electrode on different planes.
In accordance with a preferred embodiment of the present invention, the first electrode is disposed on the outer surface of the dielectric substrate and the second electrode covered with a dielectric layer is disposed on the inner surface of the dielectric substrate.
In accordance with a preferred embodiment of the present invention, the first electrode is disposed on the outer surface of the dielectric substrate without covering the dielectric layer and the second electrode covered with the dielectric layer is disposed on the inner surface of the dielectric substrate. The first and second electrodes are both strip type and are perpendicular each other. Also, the first electrode could be planar type.
In accordance with a preferred embodiment of the present invention, the flat fluorescent lamp further comprises a carrier substrate beneath the dielectric substrate for supporting the flat fluorescent lamp. The first electrode is disposed on the outer surface of the dielectric substrate or is disposed on one surface of the carrier substrate facing the dielectric substrate. The second electrode covered with the dielectric layer is disposed on the inner surface of the dielectric substrate. An adhesive is disposed between the dielectric substrate and the carrier substrate for connecting the two substrates.
In accordance with a preferred embodiment of the present invention, the flat fluorescent lamp further comprises a third electrode disposed on the outer surface of the upper plate, or covered with the dielectric layer on the inner surface of the upper plate.
In accordance with a preferred embodiment of the present invention, the flat fluorescent lamp further comprises a reflective layer disposed beneath the dielectric substrate so that the first electrode is disposed between the dielectric substrate and the reflective layer. Based on the concept of the present invention, the second electrode is disposed on the outer surface of the reflective layer.
Based on the concept of the present invention, the electrode pair, including the first and the second electrodes, is disposed on the different planes so that the discharge area between the two electrodes is larger than that between two electrodes on the same plane in general. Thus, the flat fluorescent lamp of the present invention provides significant improvement in luminosity.
Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
In the embodiments illustrated in the descriptions, the “inner surface” of the upper plate or the dielectric substrate indicated the surface facing the gas discharge chamber, and the “outer surface” of the upper plate or the dielectric substrate is the opposite side of the “inner surface”, respectively.
First, referring to
Similarly, referring to
In the process of ignition of the flat lamp, the electrode 206 on the outer wall of the gas discharge chamber 200 is driven so that the electrode within the gas discharge chamber 202 partially emits electrons which collide with the gas 204, and the gas 204 is ionized and excited to form plasma. After that, the excited state atoms of the plasma return to the ground state by way of emission of UV rays, and the emitted UV rays further excite the fluorescence substance 202 on the inner wall of the gas discharge chamber 200 so as to produce visible light.
In accordance with the preferred embodiment during the driving process, the electrodes 206, isolated by the dielectric substrate 200a, form an electric field within the gas discharge chamber 200, and the thickness of the dielectric substrate 200a directly affects the difficulty of the driving process. When the thickness of the dielectric substrate 200a is large, the flat lamp is more difficult to drive, and vice versa; to facilitate the driving process, a thinner dielectric material 200a is used. In contrast, the dielectric substrate 200a may be broken for the reason that the substrate 200a cannot withstand the external atmospheric pressure. Thus, in order to consider both the difficulty of the driving process and the strength of the dielectric substrate 200a, the present preferred embodiment provides a flat lamp structure, as shown in
Referring to
In accordance with the flat lamp structure, as the dielectric substrate 200a and the carrier substrate 210 are connected using the adhesive 208, the structural body constructed by the dielectric substrate 200a and the carrier substrate 210 can withstand the external atmospheric pressure, thus, as a whole, the strength of the flat lamp is enhanced.
Similarly, referring to
The flat lamp structure of the present invention is similar to that of the first preferred embodiment, and the only difference is on the design of the spacer 300.
The spacer 300 is designed out of concern for the difficulty of the driving process and the strength of the dielectric substrate 200a; the spacer 300 of the gas discharge chamber 200b can withstand the dielectric substrate 200a and the surface of the plate 200b such that the strength of the dielectric substrate 200a can be enhanced, and its breakage as a result of its inability to withstand the external atmospheric pressure will not occur.
Next, referring to
In accordance with the present invention, the dielectric substrate with controllable thickness and uniformity is used to substitute conventional dielectric layer formed from multiple screen printing process and the electrode is disposed on the outer wall of the gas discharge chamber to form external electrodes. Thus, the flat lamp structure of the present invention possesses the following advantages: (1) the replacement of the dielectric layer fabricated by multiple screen printing with the present dielectric substrate provides a simple fabrication process and the fabrication time is shortened, and the yield is improved; (2) the replacement of the dielectric layer fabricated by multiple screen printing with the present dielectric substrate alleviates the error in the fabrication process, thus improving yield and reducing production costs; and (3) excellent thickness uniformity of the dielectric substrate allows for a small difference of electric field between the individual electrodes, thus the uniformity of light emission of the flat lamp is improved.
In order to improve the longevity and efficiency of luminance, the present invention provides another preferred embodiments of the flat fluorescent lamp comprising at least an electrode pair formed by one first electrode and one second electrode, both of which are positioned on different planes.
Referring to
In accordance with the flat fluorescent lamp shown in
Assuming the first and second electrodes 306, 307 disposed on the outer and inner surfaces of the dielectric substrate 300a are represented as “A” and “B”, respectively, the arrangement of the electrode pairs shown in
As shown in
In the flat fluorescent lamp shown in
In the flat fluorescent lamp shown in
The flat fluorescent lamp shown in
The flat fluorescent lamp further comprises a carrier substrate 510 disposed beneath the dielectric substrate 500a for supporting the flat fluorescent lamp. The first electrode 506 is disposed on the outer surface of the dielectric substrate 500a or is disposed on one surface of the carrier substrate 510 facing the dielectric substrate 500a. An adhesive 508, such as glass glue, ceramic glue, UV curing adhesive or thermal curing adhesive, is disposed between the dielectric substrate 500a and the carrier substrate 510 for connecting the dielectric substrate 500a and the carrier substrate 510.
Assuming the first and the second electrodes 506 and 507 disposed on the outer and inner surfaces of the dielectric substrate 500a are represented as “A” and “B”, respectively, the arrangement of the electrode pairs shown in
Referring to
The flat fluorescent lamp shown in the
As shown in the
In the embodiments of the present invention, the first and second electrodes 706,712 are linear, strip, zigzag or other type. The second electrode 712 is parallel or perpendicular to the first electrode 706. The second electrode 712 can also be planar.
Assuming the electrode pair, i.e. the first and second electrodes 706, 712, is represented as “A” and “B”, respectively, the arrangement of the electrode pairs shown in
In the embodiments shown in FIGS. 6 to 10, the dielectric substrates 300a, 400a, 500a, 600a, 700a are dielectric material such as glass or ceramic and have a thickness of about 0.3-2 mm; the upper substrates 300b, 400b, 500b, 600b, 700b are transparent material such as glass and have a thickness of about 0.3-5 mm; electrodes 306, 307, 406, 407, 506, 507, 606, 607, 611, 706, 712 are conductive material, such as silver, copper, ITO or IZO, having a thickness of 3-50 μm; the fluorescent substance 302, 402, 502, 602, 702 can be excited by the UV light to produce visible light and have a thickness of about 2-400 μm; the discharge gas 304, 404, 504, 604, 704 includes Xe, Ne, Ar, other insert gas, mercury free gas, or a mixture thereof; the dielectric layers 309, 409, 509, 609 are made of PbO, SiO2, Bi2O3, ceramic or combinations thereof and have a thickness of about 30-400 μm; the carrier substrate 510 is glass or ceramic; the adhesive 508 is glass glue, ceramic glue, UV curing adhesive or thermal curing adhesive; and the reflective layer 718 is made of glass material doped with TiO2, Al2O3 or combinations thereof.
As the embodiments illustrated in the present invention, the edges of the upper substrate and the dielectric substrates can be connected with each other or connected by strips to form the gas discharge chambers 300, 400, 500, 600, 700. The distance between the dielectric substrate and the upper substrate is about 0.5-10 mm. At least one spacer can be optionally mounted between the dielectric layer and the upper substrate to maintain the distance.
In accordance with the flat fluorescent lamps in the all embodiments of the present invention, the electrode pair including the first and the second electrodes is disposed on the different planes. In comparison with the conventional flat lamp, the flat fluorescent lamp of this invention can produce a larger discharge area to perform a better efficiency of luminance. Furthermore, in comparison with the conventional flat lamp, the cost of dielectric material could be reduced to a half of conventional design.
While there has been shown and described what are at the present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
091137109 | Dec 2002 | TW | national |
The present application is a continuation-in-part (C.I.P.) application of U.S. patent application Ser. No. 10/604,588, filed on Jul. 31, 2003, which is entitled “FLAT LAMP STRUCTURE” which is fully incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
Parent | 10604588 | Jul 2003 | US |
Child | 11585876 | Oct 2006 | US |