1. Field of the Invention
Embodiments relate to a gas excitation light-emitting device. More particularly, embodiments relate to a gas excitation light-emitting device having reduced driving voltage and improved luminous efficiency.
2. Description of the Related Art
Plasma discharge phenomenon is employed to produce light in a variety of devices, e.g., plasma display panels (PDPs) and flat lamps.
Flat lamps may employ plasma discharge phenomenon to generate light. For example, flat lamps may be employed as a backlight for a liquid crystal display (LCD).
PDPs form images using electrical discharge, have good brightness characteristics and a wide viewing angle. PDPs display images using visible light emitted through a process of exciting a phosphor material with ultraviolet rays generated from a discharge of a discharge gas between electrodes when a direct current (DC) voltage or an alternating current (AC) voltage is applied to the electrodes.
In general, PDPs are classified as facing discharge type panels and surface discharge type panels according to the arrangement of the electrodes. In facing discharge type panels, two sustaining electrodes constituting a pair are respectively disposed on an upper substrate and a lower substrate, and thus, discharge occurs in a direction perpendicular to each of the upper substrate and the lower substrate. In the surface discharge type panels, two sustaining electrodes constituting a pair are formed on the same substrate, and thus, discharge occurs in a direction parallel to the substrate.
More particularly, in such devices, ultraviolet light may be generated when excited ionized gas atoms, e.g., Xe atoms, stabilize, i.e., electron(s) return to their original energy level. That is, such devices generally require a relatively large amount of energy to ionize the discharge gas to generate ultraviolet light. Thus, such devices generally require a relatively high driving voltage, and a luminous efficiency thereof is relatively low.
Embodiments of the invention are therefore directed to a gas excitation light-emitting device, which substantially overcomes one or more of the problems due to the limitations and disadvantages of the related art.
It is therefore a feature of an embodiment of the invention to provide a gas excitation light-emitting device with reduced power consumption.
It is therefore a separate feature of an embodiment of the invention to provide a gas excitation light-emitting device with improved luminous efficiency.
It is therefore a separate feature of an embodiment of the invention to provide a gas excitation light-emitting device in which an image may be formed using only an energy of electrons emitted when an electron accelerating layer is excited.
It is therefore a separate feature of an embodiment of the invention to provide a gas excitation light-emitting device that may be operated with a reduced driving voltage
It is therefore a separate feature of an embodiment of the invention to provide a gas excitation light-emitting device in which an exposed area of an electrode in a cell of the device may be reduced.
It is therefore a separate feature of an embodiment of the invention to provide a gas excitation light-emitting device in which an area of a phosphor layer coated in a cell of the device may be increased.
It is therefore a separate feature of an embodiment of the invention to provide a gas excitation light-emitting device in which a brightness of a phosphor layer of the device may be improved.
Embodiments of the invention may separately provide such gas excitation light-emitting devices including any one or more of the above and/or other features and/or advantages of the invention in a reflective-type or backlit-types gas excitation light-emitting device, e.g., a flat lamp, PDP, etc.
At least one of the above of and other features of the invention may be realized by providing a gas excitation light-emitting device, including a first substrate and a second substrate that are disposed facing each other by a predetermined interval, wherein a plurality of cells are defined between the first substrate and the second substrate, an excitation gas in each of the cells, a phosphor layer in each of the cells, a plurality of electrodes disposed between the first substrate and the second substrate, and an electron accelerating layer emitting an E-beam in each of the cells, wherein, for each of the cells, the electron accelerating layer excites the excitation gas in the cell when a voltage is applied to corresponding ones of the electrodes of the cell, the phosphor layer is spaced apart from the electrodes of the cell, and the phosphor layer is arranged in a first portion of the cell other than a second portion of the cell between corresponding ones of the electrodes of the cell.
The phosphor layer may be formed on an entire cell-facing surface portion of at least one of the first substrate and the second substrate of the respective cell.
The electron accelerating layer may include oxidized porous silicon.
The device may include a first barrier rib partially extending between adjacent ones of the cells and protruding from the second substrate, wherein a portion of the respective phosphor layer also covers a portion of the barrier rib.
A portion of the phosphor layer on the barrier rib may be thicker than a portion of the phosphor layer on the second substrate.
For each of the cells, the electrodes may include a first electrode and a second electrode, wherein the first electrode may be arranged on the first substrate with the electron accelerating layer stacked thereon, and the second electrode may be arranged between adjacent ones of the cells and stacked with the first barrier rib between the first substrate and the second substrate.
The second electrode may protrude into the cell relative to the first barrier rib.
The device may further include a first dielectric material layer between the first substrate and the second electrode.
The device may further include a third electrode between the first barrier rib and the first substrate.
The device may further include a second dielectric material layer between the second electrode and the third electrode.
The device may further include a reflective layer formed between the second substrate and the phosphor layer.
At least one of the electrodes may be arranged between adjacent ones of the cells, and the device further may further include a second barrier rib between respective portions of the at least one of the electrodes between adjacent ones of the cells.
At least one dielectric material layer may also be arranged between adjacent ones of the cells and between the at least one electrode and the first substrate, and the second barrier rib may extend between respective portions of the at least one dielectric material layer.
The device may further include a first barrier rib arranged on the at least one electrode, wherein the first barrier rib, the at least one second electrode and the at least one dielectric material layer are stacked on each other between the first and second substrates, and the second barrier rib protrudes from the first substrate and extends between the respective portions of the at least one electrode and the respective portions of the at least one dielectric material layer.
For each of the cells, the respective phosphor layer may be arranged on one of an upper portion and a lower portion of the cell, and respective corresponding portions of the electrodes may be arranged on the other of the upper portion and the lower portion of the cell.
The first portion may be one of an upper portion and a lower portion of the cell, and the second portion may be the other of the upper portion and the lower portion of the cell.
At least one of the above of and other features of the invention may be realized by providing a gas excitation light-emitting device, including a first substrate and a second substrate that are disposed facing each other by a predetermined interval, wherein a plurality of cells are defined between the first substrate and the second substrate, an excitation gas fills the cells, a phosphor layer disposed in each of the cells, a plurality of electrodes disposed between the first substrate and the second substrate, and an electron accelerating layer emitting an E-beam that excites the excitation gas in the cells, wherein the electrodes are disposed on one of the first substrate and the second substrate, the phosphor layer is disposed on the other one of the first substrate and the second substrate, and the phosphor layer is spaced apart from the electrodes.
A gas excitation light-emitting device including a first substrate and a second substrate which are disposed facing each other by a predetermined interval, wherein a plurality of cells are formed between the first substrate and the second substrate, an excitation gas filled into the cells, a phosphor layer formed on an inner wall of the cells, a first electrode and a second electrode formed on the substrate as a pair that define a discharge space that is defined between the first substrate and the second substrate, so as to form the cells, a third electrode formed inside the first electrode; and a first electron accelerating layer formed between the first substrate and the third substrate, and which emits a first E-beam that excites the excitation gas in the cells when a voltage is applied to the first electrode and the third electrode.
The phosphor layer may be formed on the entire surface of one of the first substrate and the second substrate.
The device may further include a fourth electrode formed inside the second electrode, and a second electron accelerating layer formed between the second electrode and the fourth electrode, and which emits a second E-beam that excites the excitation gas in the cell when a voltage is applied to the second electrode and the fourth electrode.
The first electron accelerating layer and the second electron accelerating layer may include oxidized porous silicon.
Each of the third electrode and the fourth electrode may have a mesh structure.
The above and other features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the attached drawings, in which:
Korean Patent Application No. 10-2007-0041617, filed on Apr. 27, 2007, in the Korean Intellectual Property Office, and entitled: “Gas Excitation Light-Emitting Device,” is incorporated by reference herein in its entirety.
Exemplary embodiments will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated. Embodiments may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
In the figures, the dimensions of layers and regions may be exaggerated for clarity of illustration. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when an element is referred to as being “on,” “below” or “above” another element, it can be directly “on,” “below” or “above” the other element, or intervening elements may also be present. In addition, it will also be understood that, unless specified otherwise, when an element is referred to as being “between” two elements, it can be the only element between the two elements, or one or more intervening elements may also be present. Like reference numerals refer to like elements throughout the specification.
Referring to
The first substrate 110, e.g., a lower substrate, and the second substrate 120, e.g., an upper substrate, may be disposed facing each other by a predetermined interval. The first substrate 110 may be formed of a transparent glass substrate. The second substrate 120 may be formed of a transparent glass substrate.
The cell(s) 114 may be formed between the first substrate 110 and the second substrate 120. Each cell 114 may correspond to a respective space between the first substrate 110 and the second substrate 120. More particularly, e.g., each respective space may be at least partially defined by a combination of the first substrate 110, the second substrate 120 and corresponding portions of electrode(s), dielectric material layer(s) and/or barrier rib(s).
The barrier rib(s) 113 may prevent and/or reduce electrical and optical crosstalk between the cells 114. The barrier rib 113 may be interposed between the second electrode 132 and the second substrate 120 to define respective cells 114. The barrier rib 113 may have a striped structure or a matrix structure. The barrier rib 113 may be formed on the second electrode 132 using, e.g., a printing method or the like. In some embodiments, the barrier rib(s) 113 may be integrally formed on a side of the second substrate 120. The barrier rib(s) 113 may protrude from a side of the second substrate 120 facing the first substrate 110. Respective portions of the barrier rib(s) may correspond to a border(s) between adjacent ones of the cells 114. In some embodiments, the barrier rib(s) 113 may protrude from the second substrate 120 so as to partially and/or completely define cell-facing-surface portion(s) 120a of the second substrate 120, i.e., surface portion(s) of second substrate 120 overlapping the respective cell 114. In some embodiments, a barrier rib may not be formed. In such embodiments, e.g., the second electrode 132 and/or the third electrode 133 may at least partially define the respective cells 114. More particularly,
In some embodiments, the second electrode 132, the third electrode 133 and/or the barrier rib 113 may be at least partially stacked on each other. More particularly, in some embodiments of the invention, a combination of the barrier rib(s) 113, the electrode(s), e.g., the second and third electrodes 132, 133, and the dielectric material layer(s), e.g., the first and second dielectric material layers 151, 152 may be stacked between the first and second substrates 110, 120. In some embodiments, the stacked combination of the barrier rib, the electrode(s) and the dielectric material layer(s) may have a height H, along a y-direction, equal to the interval between the first substrate 110 and the second substrate 120. For example, in some embodiments, a stacked combination of corresponding ones of the barrier rib(s) 113, the second electrode 132, the third electrode 133, the first dielectric layer 151 and the second dielectric layer 152 may have a height H equal to the interval between the first and second substrates 110, 120.
A phosphor layer 115 corresponding to one of red (R), green (G) and blue (B) light may be coated on inner wall(s)/surface(s) of the respective cell 114, e.g., on the barrier rib(s) 113 and/or the substrates 110, 120. In the exemplary embodiment illustrated in
Further, in general, a brightness of a phosphor layer may be improved by increasing an area thereof. Additionally, in general, a quantity of electrons emitted from an electron accelerating layer directly influences a brightness of a cell and an efficiency of the electrons. However, phosphor layers are generally poor conductors, and when the phosphor layer is between electrodes, e.g., the first electrode 131 and the second or third electrodes 132, 133, electrons may accumulate on a surface of the phosphor layer and brightness may be reduced, i.e., efficiency may be reduced. More particularly, when the phosphor layer is arranged along a direct path between corresponding ones of the electrodes, electrons may accumulate on a surface of the phosphor layer and brightness may be reduced. Therefore, in devices in which a phosphor layer is arranged between electrodes, a thickness and/or area of the phosphor is generally reduced.
In embodiments of the invention, a phosphor layer, e.g., the phosphor layer 115, may be arranged so as not to be between and/or in contact with respective electrodes. For example, as discussed above, in the exemplary embodiment shown in
In some embodiments, the exemplary gas excitation light-emitting device 100 of
At least relative to cases in which an electrode, e.g., a second electrode, is formed on a second substrate, in some embodiments of the invention, e.g., the exemplary gas excitation light-emitting device 100 of
The cell(s) 114 may be filled with an excitation gas including, e.g., Xe. The excitation gas may be a gas that is excited by external energy such as an E-beam so as to emit ultraviolet rays. However, the excited gas according to embodiments may function as a discharge gas.
The first electrode(s) 131 may be formed on the first substrate 110, and a respective portion(s) thereof may correspond to the respective cell(s) 114 adjacent thereto. The third electrode 133 and the second electrode 132 may be stacked on a side, e.g., a same side, of the first electrode 131. More particularly, in some embodiments, a respective one the first electrodes 131 and a respective one of the second electrodes 132 extending along one side of a respective one of the respective cell 140 may be associated with that cell 140, while another one of the first electrodes 131 and another one of the second electrodes 132 adjacent to another side of that cell 140 may be associated with another one of the cells 140 of the gas excitation light-emitting device 100. However, in embodiments in which the second electrode 132 and/or the third electrode 133 may have portions exposed to adjacent ones of the cells 114, as illustrated in
Each of the first, second and third electrodes 131, 132, 133 may have, e.g., a striped pattern. In some embodiments, the first, second and third electrodes 131, 132, 133 may extend parallel and/or substantially parallel to each other. The first electrode 131, the second electrode 132 and the third electrode 133 may correspond to a cathode, an anode and a grid electrode, respectively. In some embodiments, all electrodes, e.g., the first electrode 131, the second electrode 132 and/or the third electrode 133 may be formed on a same substrate, e.g., the first substrate 110 and/or a same portion, e.g., 114a, of the cell 114. For example, referring to
Referring to
Embodiments of the invention may provide a gas excitation light-emitting device in which an area and/or thickness of a phosphor layer may be increased by not arranging the phosphor layer between and/or in contact with corresponding electrodes of a cell that may function together. Accordingly, embodiments may enable a brightness of a phosphor layer in a cell to be improved. Embodiments of the invention may separately provide a gas excitation light-emitting device in which corresponding electrodes of a cell that may function together are arranged in such a manner to reduce a surface area of the cell corresponding to the electrodes, while maintaining and/or improving conductivity characteristics of the electrodes.
Referring still to
The electron accelerating layer 140 may be formed on the first electrode 131. The electron accelerating layer 140 may include any material that accelerates electrons so as to generate an E-beam. In some embodiments, the electron accelerating layer 140 may include oxidized porous silicon (OPS), e.g., oxidized porous poly silicon, oxidized porous amorphous silicon, etc. In some embodiments, the electron accelerating layer 140 may include a carbon nanotube (CNT) through which visible rays may be transmitted.
In the exemplary embodiment illustrated in
The electron accelerating layer 140 may accelerate electrons incoming from the first electrode 131 so as to emit an E-beam into the cell(s) 114 when at least a predetermined voltage is applied to each of the first electrode 131 and the third electrode 133 corresponding to the respective cell 114. The E-beam emitted into the respective cell(s) 114 may excite an excitation gas that may stabilize and generate ultraviolet rays that excite the phosphor layer 115. The excited phosphor layer 115 may generate visible rays, which may be emitted towards the second substrate 120 in order to form an image.
The E-beam may have an energy that may be sufficient for and/or greater than an energy required for exciting the excitation gas. In some cases, the E-beam may have an energy less than an energy required for ionizing the excitation gas. A voltage may be applied to the first electrode 131 and the third electrode 133 so as to have an optimized electron energy that can excite the E-beam.
The electron accelerating layer 140 may increase electron emission of a cathode such as the first electrode 131 and, accordingly, may reduce a discharge voltage during discharge of the gas excitation light-emitting device 100. The electron accelerating layer 140 may reduce an amount of energy employable for ionization and ion-acceleration and, accordingly, may improve the efficiency of the gas excitation light-emitting device 100. The electron accelerating layer 140 may provide all or substantially all of the electrons required for emitting light. Thus, during operation of some embodiments, electric discharge may not occur, and loss due to ions may be completely and/or substantially completely prevented.
More particularly, e.g., in
Accordingly, an E-beam, which is emitted into the cell 114 by the electron accelerating layer 140, may have an energy in the range of 8.28 eV to 12.13 eV in order to excite Xe. In this case, the E-beam may have an energy equal to and/or within the range of 8.28 eV to 9.57 eV or 8.28 eV to 8.45 eV. In addition, the E-beam may have an energy equal to and/or within the range of 8.45 eV to 9.57 eV.
Referring again to
The gas excitation light-emitting device 200 of
Referring to
Referring to
The dielectric material layer 250 may be interposed between the first electrode 231 and the second electrode 232, via the first substrate 210, so as to insulate the first electrode 231 from the second electrode 232. The first electrode 231 may correspond to a cathode, and the second electrode 232 may correspond to an anode.
The barrier rib 213 may be formed on the second electrode 232, and the barrier rib 213 may be interposed between the second electrode 232 and the second substrate 220.
As illustrated in
Referring to
That is, the exemplary gas excitation light-emitting device 300 of
When a predetermined voltage is applied to the first electrode 331 and third electrode 333, the electron accelerating layer 340 may accelerate electrons from the first electrode 331 to emit an E-beam through the third electrode 333 to an inside of the respective cell 314. The excited beam emitted into the respective cell 314 may excite the gas in the cells 314 such that the gas is stabilized to generate ultraviolet rays. In addition, the ultraviolet rays may excite a phosphor layer 315 so as to generate visible rays that are emitted towards the second substrate 320 to form an image.
The gas excitation light-emitting device 400 of
Referring to
The exemplary gas excitation light-emitting device 400 illustrated in
In the exemplary embodiment 400 of
That is, the phosphor layer 415 may be formed to have an appropriate thickness so that visible rays are not transmitted through the phosphor layer 415, and those that are transmitted may be reflected back by the reflective layer 460 through the phosphor layer 415 so as to be emitted towards the first substrate 410 to form an image(s). In some embodiments, a thickness of the phosphor layer 415 in such a reflective structure may be equal to and/or within a range of about 30 μm to about 60 μm.
In some embodiments, the reflective layer 460 may not be provided. In some embodiments, the reflective layer 460 may be provided between the second substrate 420 and the phosphor layer 415. In such embodiments, a part of the visible rays transmitted through the phosphor layer 415 may be reflected by the reflective layer 460 so that the visible rays may be emitted towards the first substrate 410. The reflective layer 460 may include, e.g., aluminum, silver and/or calcium. The reflective layer 460 may simultaneously function as the second electrode 432, such that the second electrode 432 may not be provided between the barrier rib(s) 413 and the first substrate 410.
In some embodiments of a reflective structure, the reflective structure may include a phosphor layer having a thickness that is greater than a thickness of a phosphor layer employed in a backlit structure. Thus, brightness and an efficiency of such a reflective structure may be improved. Further, the gas excitation light-emitting device 400 may include the reflective layer 460, and thus, luminous efficiency thereof may be further improved.
Referring to
The gas excitation light-emitting device 500 of
More particularly, in the exemplary gas excitation light-emitting device 100 of
More particularly, in the gas excitation light-emitting device 500 of
Similarly, in the gas excitation light-emitting device 500 of
Accordingly, in some embodiments of the invention, when, e.g., a first voltage is applied to the second electrode 632a of the cell 614a, a separate voltage (same or different from the first voltage) may be applied to the second electrode 632b of the cell 614b and another separate voltage (same or different from the first voltage) may be applied to the second electrode 632c of the cell 614c. Similarly, in some embodiments of the invention, when, e.g., a first voltage is applied to the third electrode 633a of the cell 614a, a separate voltage (same or different from the first voltage) may be applied to the third electrode 633b of the cell 614b and another separate voltage (same or different from the first voltage) may be applied to the second electrode 633c of the cell 614c.
Although the gas excitation light-emitting device 500 is illustrated as a three electrode structure, including the first electrodes 631a, 631b, 631c, the second electrodes 632a, 632b, 632c and the third electrodes 633a, 633b, 633c, embodiments of the invention are not limited thereto. That is, the gas excitation light-emitting device 500 may be used, e.g., as a two electrode structure. Also, similar to the three electrode structure illustrated in
In the gas excitation light-emitting device 600 of
Referring to
The first electrode 531 and the second electrode 532 may be formed between the first substrate 510 and the second substrate 520 in respective cells 514. The first and second electrodes 531 and 532 may be respectively formed on opposing sides of each of the cells 514. The first and second electron accelerating layers 541 and 542 may be respectively formed on inner surfaces of the first and second electrodes 531 and 532. The third and fourth electrodes 533 and 534 may be respectively formed on the first and second electron accelerating layers 541 and 542. The first and second electron accelerating layers 541, 542 may be formed of any material that accelerates electrons so as to generate an E-beam, e.g., OPS.
The first electron accelerating layer 541 may emit a first E-beam (E1-beam) into the respective cell(s) 514 when a predetermined voltage is applied to each of corresponding ones of the first electrode 531 and the third electrode 533. The second electron accelerating layer 542 may emit a second E-beam (E2-beam) into the cells 514 when a predetermined voltage is applied to each of the second electrode 532 and the fourth electrode 534. The E1-beam and the E2-beam are alternately emitted into the cells 514 when an alternating current voltage is applied between the first electrode 531 and the second electrode 532. Each of the E1-beam and the E2-beam excites an excitation gas that is stabilized to generate ultraviolet rays exciting the phosphor layer 515. Accordingly, each of the E1-beam and the E2-beam may have an energy that is greater than the energy required for exciting the excitation gas and less than an energy required for ionizing the excitation gas. In particular, each of the E1-beam and the E2-beam may have an energy equal to and/or within a range of about 8.28 eV to about 12.13 eV, which may be employed to excite Xe.
The third and fourth electrodes 533 and 534 may be formed in a mesh structure so that electrons accelerated by the first and second electron accelerating layers 541 and 542 may be easily emitted into the cells 514. The first and second electron accelerating layers 541 and 542 may be formed so as to at least partially define a cell space, which is defined between the first substrate 510 and the second substrate 520, and corresponds to respective ones the cells 514. However, embodiments are not limited thereto. For example, in some embodiments, a plurality of barrier ribs (not shown) may be further formed between the first substrate 510 and the second substrate 520 so as to define a cell space, which is defined between the first substrate 510 and the second substrate 520 corresponding to each of the cells 514.
In the gas excitation light-emitting device 600 of
As described above, in a conventional plasma display panel and flat lamp in which plasma discharge is used, a relatively large amount of energy is necessary to ionize a discharge gas. Embodiments of the invention may enable an image to be formed using only an energy of electrons emitted when an electron accelerating layer is excited.
Embodiments of the invention may separately further reduce a driving voltage of such gas excitation light-emitting devices.
Embodiments of the invention may separately further improve luminous efficiency of such gas excitation light-emitting devices as compared to conventional devices, e.g., conventional plasma display panel(s) and/or conventional flat panel(s) in which plasma discharge is employed.
Embodiments of the invention may separately enable an exposed area of an electrode in a cell of such gas excitation light-emitting devices to be reduced.
Embodiments of the invention may separately enable an area of a phosphor layer coated in a cell of such gas excitation light-emitting devices to be increased.
Embodiments of the invention may separately enable a brightness of a phosphor layer of such gas excitation light-emitting devices to be improved.
Embodiments of the invention may separately provide such gas excitation light-emitting devices including any one or more of the above and/or other features and/or advantages of the invention in a reflective-type or backlit-types gas excitation light-emitting device, e.g., a flat lamp, PDP, etc.
Exemplary embodiments of the invention have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.
Number | Date | Country | Kind |
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10-2007-0041617 | Apr 2007 | KR | national |