This application claims priority to and the benefit of Korean Patent Application No. 10-2004-0108412, filed on Dec. 18, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a display device with reduced driving voltage and increased luminous efficiency.
2. Discussion of the Background
Plasma display panels (PDPs) are a type of flat display device that display an image by the use of an electric discharge. PDPs enjoy wide popularity due to their exceptional brightness and wide viewing angle. PDPs emit visible light by a process where direct current (DC) or alternate current (AC) voltages are applied to electrodes with gas between them. The voltage difference excites the gas and causes it to emit ultraviolet rays. The ultraviolet rays in turn excite a phosphor material and cause it to emit visible light.
The two most common PDP electrode structures are the facing discharge structure and the surface discharge structure. In the facing discharge structure, a pair of sustain electrodes are disposed on an upper substrate and a lower substrate, respectively, and a discharge is generated perpendicular to the substrate. In the surface discharge structure, a pair of sustain electrodes are disposed on the same substrate and a discharge is generated parallel to the substrate.
Referring to
The upper substrate 20 is transparent and is coupled to the lower substrate 10. A pair of sustain electrodes 21a and 21b are formed perpendicular to the address electrodes 11 on is the lower surface of the upper substrate 20 of each cell 14. The sustain electrodes 21a and 21b may be formed of a conductive material that is also capable of transmitting visible light, such as indium tin oxide (ITO). Narrow bus electrodes 22a and 22b are formed of metal on the lower surface of the sustain electrodes 21a and 21b to reduce the line resistance of the sustain electrodes 21a and 21b. The sustain electrodes 21a and 21b and the bus electrodes 22a and 22b are covered by a transparent second dielectric layer 23. A protection layer 24 is formed of MgO on the lower surface of the second dielectric layer 23. The protection layer 24 prevents damage to the second dielectric layer 23 by sputtering plasma particles and reduces the required discharge voltage by emitting secondary electrons.
An address discharge and a sustain discharge must be generated to drive the PDP. The address discharge occurs between the address electrode 11 and one of the pair of the sustain electrodes 21a and 21b. The sustain discharge is caused by a potential difference between the pair of sustain electrodes 21a and 21b and excites the discharge gas, which emits ultraviolet rays that in turn excite a phosphor layer 15 that generates visible light. The visible light is emitted through the upper substrate and forms the image displayed by the PDP.
Plasma discharge can also be used in a flat lamp to produce a back-light for a liquid crystal display (LCD).
Referring to
Discharge electrodes for generating plasma discharge in each discharge cell are formed on the lower substrate 50 and the upper substrate 60. A first lower electrode 51a and a second lower electrode 51b are formed on the lower surface of the lower substrate 50 in each discharge cell 54. A first upper electrode 61a and a second upper electrode 61b are formed on the upper surface of the upper substrate 60 in each discharge cell 54. Discharge does not occur between the first lower electrode 51a and the first upper electrode 61a, or between the second lower electrode 51b and the second upper electrode 61b because they are at the same potential. A surface discharge occurs parallel to the lower substrate 50 and the upper substrate 60 because there is a potential difference between the first lower electrode 51a and the second lower electrode 51b and between the first upper electrode 61a and second upper electrode 61b.
A major drawback of a conventional plasma display panel and flat lamp is that they require a large amount of energy to ionize the discharge gas to generate ultraviolet rays. Because of this, the conventional plasma display panel and the flat lamp require a high driving voltage and have a low luminous efficiency.
The present invention provides a display device that uses electron accelerating layers in conjunction with electrodes at different voltages to emit electron beams with energy levels sufficient to excite a gas, which emits ultraviolet rays that in turn excite a light emitting layer to emit visible light. The use of electron accelerating layers makes it possible to excite the gas using a lower driving voltage and achieve an improved luminous efficiency than can be achieved by conventional display devices.
Additional features of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention.
The present invention discloses a display device that includes a first substrate and a second substrate opposing each other and having a space between them, a cell positioned between the first substrate and the second substrate, a first electrode positioned to correspond to the cell, a second electrode positioned to correspond to the cell, a first electron accelerating layer positioned on the first electrode and being capable of emitting a first electron beam into the cell, a gas inside the cell and being capable of generating ultraviolet rays when excited by the first electron beam, and a light emitting layer positioned inside the cell and being capable of generating visible light when excited by the ultraviolet rays.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention.
The invention is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure is thorough, and will fully convey the scope of the invention to those skilled in the art. Flat display devices and flat lamps are described as the exemplary display devices according to the present invention, but the present invention is not limited thereto. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity.
It will be understood that when an element such as a layer, film, region or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.
Referring to
A plurality of barrier ribs 113 are formed between the first substrate 110 and the second substrate 120 to form a plurality of cells 114 and prevent electrical and optical cross-talk between the cells 114. Red, green, and blue light emitting layers 115 may be coated on the inner walls of the cells 114. Depending on the material used, the light emitting layers 115 generate visible light when excited by either UV rays or electrons. A gas that may include Xe fills the cells 114. The gas may be a discharge gas that generates ultraviolet rays when excited by external energy such as an electron beam.
A first electrode 131 is formed in each cell 114 on the upper surface of the first substrate 110, and a second electrode 132 is formed in each cell 114 on the lower surface of the second substrate 120 to cross the first electrode 131. In this exemplary embodiment, the first electrode 131 and the second electrode 132 are a cathode electrode and an anode electrode, respectively. The second electrode 132 may be formed of a transparent conductive material such as ITO to transmit visible light. A dielectric layer (not shown) may be formed on the second electrode 132.
An electron accelerating layer 140 is formed on the upper surface of the first electrode 131. A third electrode 133, which is a grid electrode, is formed on the electron accelerating layer 140. The electron accelerating layer 140 may be formed of any material that can generate an electron beam (E-beam) by accelerating electrons. One example of such a material is oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous poly silicon or oxidized porous amorphous silicon.
The electron accelerating layer 140 emits an E-beam into the cell 114 through the third electrode 133 by accelerating electrons flowing from the first electrode 131 when a voltage is applied to the first electrode 131 and the third electrode 133 (and/or the second electrode 132). The E-beam excites the gas, which generates ultraviolet rays while stabilizing. The ultraviolet rays in turn excite the light emitting layer 115, which generates visible light to form an image when the light passes through the second substrate 120.
The E-beam may have an energy higher than the energy required to excite the gas but lower than the energy required to ionize the gas. The voltage needed for the optimal electron energy to excite the gas is applied to the first electrode 131 and the third electrode 133 (and/or the second electrode 132).
Referring to
Accordingly, in the present invention, an E-beam emitted into a cell 114 by the electron accelerating layer 140 may have an energy of about 8.28 eV to about 12.13 eV, preferably about 8.28 eV to about 9.57 eV, and more preferably about 8.28 to about 8.45. Alternatively, the E-beam may have an energy of about 8.45 eV to about 9.57 eV.
Referring to
An E-beam is emitted into the cell 114 through the electron accelerating layer 140 by the voltages applied to the first electrode 131 and the third electrode 133. The emitted E-beam is accelerated toward the second electrode 132 by the voltages applied to the third electrode 133 and the second electrode 132. The gas is excited by this process. The gas can be controlled to a discharge state by adjusting the voltage of the second electrode 132. Alternatively, the second electrode 132 can be grounded, as depicted in
Referring to
Referring to
Referring to
A first electrode 231 is formed on the upper surface of the first substrate 210 in each cell 214, and a second electrode 232 is formed on the lower surface of the second substrate 220 in each cell 214 to cross the first electrode 231. A first electron accelerating layer 241 and a second electron accelerating layer 242 are formed on the first electrode 231 and the second electrode 232, respectively. A third electrode 233 and a fourth electrode 234 are formed on the first electron accelerating layer 241 and the second electron accelerating layer 242, respectively. The first electron accelerating layer 241 and the second electron accelerating layer 242 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 231 and the third electrode 233 (and/or the second electrode 232), electrons flow through the first electrode 231 to the first electron accelerating layer 241. The first electron accelerating layer 241 accelerates the electrons to emit a first electron beam E1-beam into the cell 214 through the third electrode 233. When a voltage is applied to the second electrode 232 and the fourth electrode 234 (and/or the first electrode 231), the second electron accelerating layer 242 accelerates electrons flowing in from the second electrode 232 and emits a second electron beam E2-beam into the cell 214 through the fourth electrode 234. The alternating current causes the first electron accelerating layer 241 and the second electron accelerating layer 242 to alternately emit electron beams into the cell 214. The first and second electron beams excite the gas, which in turn generates ultraviolet rays that excite the light emitting layer 215. The first and second electron beams may have an energy greater than the energy required to excite the gas but less than the energy required to ionize the gas.
The second electrode 232 and the fourth electrode 234 may be formed of a transparent conductive material such as ITO to transmit visible light. The third electrode 233 and the fourth electrode 234 may be formed in a mesh structure so that electrons accelerated by the first and second electron accelerating layers 241 and 242 can be readily emitted into the cell 214. A plurality of address electrodes (not shown) may be formed on either the first substrate 210 or the second substrate 220.
Referring to
Referring to
A first electrode 331 and a second electrode 332 are formed between the first substrate 310 and the second substrate 320 in each cell 314. In this exemplary embodiement, the first electrode 331 and the second electrode 332 are located on either side of the cell 314. The first electron accelerating layer 341 and the second electron accelerating layer 342 are formed on the inner surface of the first electrode 331 and the second electrode 332, respectively. The third electrode 333 and the fourth electrode 334 are formed on the first electron accelerating layer 341 and the second electron accelerating layer 342, respectively. The first electron accelerating layer 341 and the second electron accelerating layer 342 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 331 and the third electrode 333 (and/or the second electrode 332), the first electron accelerating layer 341 emits a first electron beam E1-beam into the cell 314. When a voltage is applied to the second electrode 332 and the fourth electrode 334 (and/or the first electrode 331), the second electron accelerating layer 342 emits a second electron beam E2-beam into the cell 314. An alternating current is applied between the first electrode 331 and the second electrode 332, which causes the first and second electron beams to be alternately emitted into the cell 314. The first and second electron beams excite the gas, which generates ultraviolet rays that in turn excite a light emitting layer 315. The first and second electron beams may have an energy greater than the energy required to excite the gas but less than the energy required to ionize the gas.
The third electrode 333 and the fourth electrode 334 may be formed in a mesh structure so that electrons accelerated by the first electron accelerating layer 341 and the second electron accelerating layer 342 can be readily emitted into the cell 314. The first electron accelerating layer 341 and the second electron accelerating layer 342 may serve to form the cells 314 by defining a space between the first substrate 310 and the second substrate 320. A plurality of barrier ribs (not shown) may further be formed between the first substrate 310 and the second substrate 320 to define the cells 314.
The voltage waveforms shown in
Referring to
A plurality of address electrodes 411 are formed on the upper surface of the first substrate 410. The address electrodes 411 are covered by a dielectric layer 412. A first electrode 431 and a second electrode 432 are formed on the lower surface of the second substrate 420 in each cell 414. The first electrode 431 and the second electrode 432 are formed to cross the address electrodes 411. A first electron accelerating layer 441 and a second electron accelerating layer 442 are formed on the lower surfaces of the first electrode 431 and the second electrode 432, respectively. A third electrode 433 and a fourth electrode 434 are formed on the lower surfaces of the first electron accelerating layer 441 and the second electron accelerating layer 442, respectively. The first electron accelerating layer 441 and the second electron accelerating layer 442 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 431 and the third electrode 433 (and/or the second electrode 432), the first electron accelerating layer 441 emits a first electron beam E1-beam into the cell 414. When a voltage is applied to the second electrode 432 and the fourth electrode 434 (and/or the first electrode 431), the second electron accelerating layer 442 emits a second electron beam E2-beam into the cell 414. An alternating current applied between the first electrode 431 and the second electrode 432 causes the first electron beam and the second electron beam to be alternately emitted into the cell 414. The first electron beam and the second electron beam excite the gas, which generates ultraviolet rays that in turn excite a light emitting layer 415. The first electron beam and the second electron beam may have an energy greater than the energy required to excite the gas but less than the energy required to ionize the gas.
The first electrode 413, second electrode 432, third electrode 433, and fourth electrode 434 may be formed of a transparent conductive material such as ITO to transmit visible light. The third electrode 433 and the fourth electrode 434 may be formed in a mesh structure so that electrons accelerated by the first electron accelerating layer 441 and the second electron accelerating layer 442 can be readily emitted into the cell 414.
The voltage waveforms shown in
Referring to
A first electrode 531 is formed on the upper surface of the first substrate 510 in each cell 514, and a second electrode 532 is formed on the lower surface of the second substrate 520 in each cell 514 parallel to the first electrode 531. The first electrode 531 and the second electrode 532 are a cathode electrode and an anode electrode, respectively. The second electrode 532 may be formed of a transparent conductive material such as ITO for transmitting visible light, and may be formed in a mesh structure.
An electron accelerating layer 540 is formed on the upper surface of the first electrode 531, and a third electrode 533, which is a grid electrode, is formed on the upper surface of the electron accelerating layer 540. The electron accelerating layer 540 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 531 and the third electrode 533 (and/or the second electrode 532), the electron accelerating layer 540 emits an electron beam E-beam into the cell 514 through the third electrode 533 by accelerating electrons flowing from the is first electrode 531. The electron beam emitted into the cell 514 excites a gas, which generates ultraviolet rays. The ultraviolet rays in turn excite the light emitting layers 515, which emit visible light toward the second substrate 520. The third electrode 533 may be formed in a mesh structure so that electrons accelerated by the electron accelerating layer 540 can be readily emitted into the cell 514. The electron beam may have an energy greater than the energy required to excite the gas but less than the energy required to ionize the gas.
The waveforms shown in
Referring to
A first electrode 631 is formed on the upper surface of the first substrate 610 in each cell 614, and a second electrode 632 is formed on the lower surface of the second substrate 620 in each cell 614 parallel to the first electrode 631. A first electron accelerating layer 641 and a second electron accelerating layer 642 are formed on the first electrode 631 and the second electrode 632, respectively. A third electrode 633 and a fourth electrode 634 are formed on the first electron accelerating layer 641 and the second electron accelerating layer 642, respectively. The first electrode accelerating layer 641 and the second electron accelerating layer 642 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 631 and the third electrode 633 (and/or the second electrode 632), the first electron accelerating layer 641 emits a first electron beam E1-beam into the cell 614 through the third electrode 633 by accelerating electrons that enter through the first electrode 631. When a voltage is applied to the second electrode 632 and the fourth electrode 634 (and/or the first electrode 631), the second electron accelerating layer 642 emits a second electron beam E2-beam into the cell 614 through the fourth electrode 634 by accelerating electrons that enter through the second electrode 632. An alternating current applied between the first electrode 631 and the second electrode 632 causes the first electron beam and the second electron beam to be alternately emitted into the cell 614. The first electron beam and the second electron beam excite the gas, which generates ultraviolet rays that in turn excite a light emitting layer 615. The first electron beam and the second electron beam may have an energy greater than the energy required to excite the gas but less than the energy required to ionize the gas.
The second electrode 632 and the fourth electrode 634 may be formed of a transparent conductive material such as ITO to transmit visible light. The third electrode 633 and the fourth electrode 634 may be formed in a mesh structure so that electrons accelerated by the first electron accelerating layer 641 and the second electron accelerating layer 642 can be readily emitted into the cells 614.
The voltage waveforms shown in
Referring to
A first electrode 731 and a second electrode 732 are formed between the first substrate 710 and the second substrate 720 in each cell 714. The first electrode 731 and the second electrode 732 are located on either side of the cell 714. A first electron accelerating layer 741 and a second electron accelerating layer 742 are formed on the inner walls of the first electrode 731 and the second electrode 732, respectively. A third electrode 733 and a fourth electrode 734 are formed on the first electron accelerating layer 741 and the second electron accelerating layer 742, respectively. The first electron accelerating layer 741 and the second electron accelerating layer 742 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 731 and the third electrode 733 (and/or the second electrode 732), the first electron accelerating layer 741 emits a first electron beam E1-beam into the cell 714. When a voltage is applied to the second electrode 732 and the fourth electrode 734 (and/or the first electrode 731), the second electron accelerating layer 742 emits a second electron beam E2-beam into the cell 714. An alternating current applied between the first electrode 731 and the second electrode 732 causes the first electron beam and the second electron beam to be alternately emitted into the cell 714. The first electron beam and the second electron beam excite the gas, which generates ultraviolet rays that in turn excite the light emitting layer 715. The first electron beam and the second electron beam may have an energy greater than the energy required to excite the gas but less than the energy required to ionize the gas.
The third electrode 733 and the fourth electrode 734 may be formed in a mesh structure so that electrons accelerated by the first electron accelerating layer 741 and the second electron accelerating layer 742 can be readily emitted into the cells 714. The first electron accelerating layer 741 and the second electron accelerating layer 742 may serve to form the cells 714 by defining a space between the first substrate 710 and the second substrate 720. At least one spacer (not shown) may further be formed between the first substrate 710 and the second substrate 720.
The voltage waveforms shown in
Referring to
A first electrode 831 and a second electrode 832 are formed on the upper surface of the first substrate 810 in each cell 814. A first electron accelerating layer 841 and a second electron accelerating layer 842 are formed on the upper surfaces of the first electrode 831 and the second electrode 832, respectively. A third electrode 833 and a fourth electrode 834 are formed on the first electron accelerating layer 841 and the second electron accelerating layer 842, respectively. The first electron accelerating layer 841 and the second electron accelerating layer 842 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 831 and the third electrode 833 (and/or the second electrode 832), the first electron accelerating layer 841 emits a first electron beam E1-beam into the cell 814. When a voltage is applied to the second electrode 832 and the fourth electrode 834 (and/or the first electrode 831), the second electron accelerating layer 842 emits a second electron beam E2-beam into the cell 814. An alternating current applied between the first electrode 831 and the second electrode 832 causes the first electron beam and the second electron beam to be alternately emitted into the cell 814. The first electron beam and the second electron beam excite the gas, which generates ultraviolet rays that in turn excite the light emitting layer 815. The first electron beam and the second electron beam may have an energy greater than the energy required to excite the gas but less than the energy required to ionize the gas.
The third electrode 833 and the fourth electrode 834 may be formed in a mesh structure so that electrons accelerated by the first electron accelerating layer 841 and the second electron accelerating layer 842 can be readily emitted into the cell 814.
The voltage waveforms shown in
Referring to
A fifth electrode 931 and a sixth electrode 932 are formed on the lower surface of the second substrate 820 in each cell 814. The fifth electrode 931 and the sixth electrode 932 are formed parallel to the first electrode 831 and the second electrode 832. The third electron accelerating layer 941 and the fourth electron accelerating layer 942 are formed on the lower surfaces of the fifth electrode 931 and the sixth electrode 932, respectively. The seventh electrode 933 and the eighth electrodes 934 are formed on the lower surfaces of the third electron accelerating layer 941 and the fourth electron accelerating layer 942, respectively. The third electron accelerating layer 941 and the fourth electron accelerating layer 942 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the fifth electrode 931 and the seventh electrode 933 (and/or the sixth electrode 932), the third electron accelerating layer 941 emits a third electron beam E3-beam into the cell 814. When a voltage is applied to the sixth electrode 932 and the eighth electrode 934 (and/or the fifth electrode 931), the fourth electron accelerating layer 942 emits a fourth electron beam E4-beam into the cell 814. An AC voltage applied between the fifth electrode 931 and the sixth electrode 932 causes the third electron beam and the fourth electron beam to be alternately emitted into the cell 814. The seventh electrode 933 and the eighth electrode 934 may be formed in a mesh structure so that electrons accelerated by the third electron accelerating layer 941 and the fourth electron accelerating layer 942 can be readily emitted into the cell 914.
Referring to
One first electrode 1031 and two second electrodes 1032 are formed in each of the cells 1014. The second electrodes 1032 are arranged on both sides of the cells 1014. The first electrode 1031 is arranged on an upper surface of the first substrate 1010.
A first electron acceleration layer 1041 and a second electron acceleration layer 1042 are formed on the inner surface of the first electrode 1031 and the second electrode 1032, respectively. A third electrode 1033 and a fourth electrode 1034 are formed on the first electron acceleration layer 1041 and the second electron acceleration layer 1042, respectively. The first electron acceleration layer 1041 and the second electron accelerating layer 1042 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a predetermined voltage is applied to the first electrode 1031 and the third electrode 1033 (and/or the second electrode 1032), the first electron accelerating layer 1041 emits a first electron beam E1-beam into the cell 1014. When a predetermined voltage is applied to the second electrode 1032 and the fourth electrode 1034 (and/or the first electrode 1031), the second electron accelerating layer 1042 emits a second electron beam E2-beam into the cell 1014. An AC voltage applied between the first electrode 1031 and the second electrode 1032 causes the first electron beam and the second electron beam to be alternately emitted into the cell 1014. The first electron beam and the second electron beam excite the gas, which generates ultraviolet rays that in turn excite the light emitting layer 1015. The first and second electron beams may have energy levels that are greater than the energy required to excite the gas but smaller than the energy required to ionize the gas.
The third electrode 1033 and the fourth electrode 1034 may be formed in a mesh structure to allow electrons accelerated by the first electron accelerating layer 1041 and the second electron accelerating layer 1042 to be readily emitted into the cells 1014. The second electron accelerating layers 1042 serve to form the cells 1014 by defining a space between the first substrate 1010 and the second substrate 1020. At least one spacer (not shown) may further be formed between the first substrate 1010 and the second substrate 1020.
The voltage waveforms shown in
Referring to
One first electrode 1131 and two second electrodes 1132 are formed in each of the cells 1114 between the first substrate 1110 and the second substrate 1120. The first electrode 1131 is arranged on an upper surface of the first substrate 1110, and the second electrodes 1132 are arranged on both sides of each of the cells 1114. The first electrode 1131 and the second electrodes 1132 extend to cross each other.
A first electron acceleration layer 1141 and a second electron acceleration layer 1142 are formed on the inner surfaces of the first electrode 1131 and the second electrode 1132, respectively. A third electrode 1133 and a fourth electrode 1134 are formed on the first electron acceleration layer 1141 and the second electron acceleration layer 1142, respectively. The first electron acceleration layer 1141 and the second electron acceleration layer 1142 may be formed of any material that can generate an electron beam by accelerating electrons, such as oxidized porous silicon. The oxidized porous silicon may be, for example, oxidized porous polysilicon or oxidized porous amorphous silicon.
When a voltage is applied to the first electrode 1131 and the third electrode 1133 (and/or the second electrode 1132), the first electron accelerating layer 1141 emits a first electron beam E1-beam into the cell 1114. When a voltage is applied to the second electrode 1132 and the fourth electrode 1134 (or the first electrode 1131), the second electron accelerating layers 1142 emit two second electron beams E2-beam into the cell 1114. An AC voltage applied between the first electrode 1131 and the second electrode 1132 cause the first electron beam and the second electron beams to be alternately emitted into the cell 1114. The first electron beam and the second electron beams excite the gas, and the gas generates ultraviolet rays, which in turn excite the light emitting layer 1115. The first electron beam and the second electron beams may have energy levels that are greater than the energy required to excite the gas but smaller than the energy required to ionize the gas.
The third electrode 1133 and the fourth electrode 1134 may be formed in a mesh structure to allow the electrons accelerated by the first electron accelerating layer 1141 and the second electron accelerating layers 1142 to be easily emitted into the cells 1114. The second electron accelerating layers 1142 serve to form the cells 1114 by defining a space between the first substrate 1110 and the second substrate 1120. A plurality of barrier ribs (not shown) may be further formed between the first substrate 1110 and the second substrate 1120.
The voltage waveforms shown in
It will be apparent to those skilled in the art that various modifications and variation can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
Number | Date | Country | Kind |
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10-2004-0108412 | Dec 2004 | KR | national |