JP2005174818A - Electron emitting element, light emitting element, and cold cathode display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electron emitting element making phosphor emit light by the electron beam emitted from a cold cathode, and to easily manufacture a light emitting element and a cold cathode display device driven by a low voltage capable of imparting a display with high precision by reducing the diameter of the electron beam irradiated on the phosphor. <P>SOLUTION: The light emitting element 60 is composed of an insulation layer 64 having an opening E on a substrate 61, a control electrode 65 formed on the insulation layer 64, an electron emitting electrode 62 formed on the substrate 61 exposed at the opening E, and a draw-out electrode 63 formed on a neighboring area of the electron emitting electrode 62. The phosphor 71 applied on a substrate 72 through an anode electrode 72 is arranged so as to face the electron emitting electrode 62 and the draw-out electrode 63. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electron-emitting device, a light-emitting device, and a cold-cathode display device, and more particularly to an electron-emitting device, a light-emitting device, and a cold-cathode display device that emits a phosphor by an electron beam emitted from the cold cathode.

  A cold cathode display device for displaying an image is provided with a plurality of light emitting elements including a cold cathode. The plurality of light emitting elements respectively correspond to subpixels having phosphors for RGB. When such a cold cathode display device is used as, for example, a high-vision display device, 6 million or more subpixels are required, and accordingly, the interval between adjacent subpixels needs to be reduced.

  Further, when an image is displayed on such a cold cathode display device, in order to prevent color mixing, it is necessary to make the beam diameter of the electron beam with respect to one subpixel equal to or less than the pitch of the subpixel.

  Next, the configuration of three conventional light emitting elements will be described with reference to FIGS. FIG. 1 is a diagram showing a two-electrode type light emitting device, FIG. 2 is a diagram showing a three-electrode type light emitting device, and FIG. 3 is a diagram showing a four-electrode type light emitting device having a focusing electrode. FIG. The “device front side” shown in FIGS. 1 to 3 indicates a side for viewing an image, and the “device rear side” indicates a side opposite to the device front side.

  Further, R1 in FIG. 2 indicates the beam diameter of the electron beam irradiated on the phosphor 27 (hereinafter referred to as beam diameter R1), and R2 in FIG. 3 indicates the electron irradiated on the phosphor 41. The beam diameter of the beam (hereinafter referred to as beam diameter R2) is shown.

  As shown in FIG. 1, a two-electrode type light emitting device 10 includes a substrate 11 and an electron-emitting device including a cold cathode 12 formed thereon, and a substrate 15 on which an electrode 14 and a phosphor 13 are formed. It is configured. Although not shown in the figure, a spacer for supporting the space between the substrate 11 and the substrate 15 is appropriately provided. The cold cathode 12 and the anode electrode 14 are formed in a matrix, and the phosphor 13 is formed so as to face the cold cathode 12. The electrode 14 is for performing both electron extraction and electron acceleration. The light emitting element 10 emits light by irradiating a fluorescent material with an electron beam B extracted and accelerated by an electrode 14 (see, for example, Non-Patent Document 1).

  As shown in FIG. 2, the three-electrode type light emitting element 20 includes a front substrate portion 26, an electron emitting element 25, and a spacer 17. The front substrate portion 26 includes a phosphor 27, an anode electrode 28, and a substrate 29, and the anode electrode 28 and the phosphor 27 are formed below the substrate 29.

  The electron-emitting device 25 includes a substrate 21, a cold cathode 22, an insulating layer 23, and an extraction electrode 24. An insulating layer 23 having an opening C and an extraction electrode 24 are formed on the substrate 21, and a cold cathode 22 is formed on the substrate 21 exposed to the opening C.

  The front substrate portion 26 and the electron emitter 25 are disposed so that the phosphor 27 and the cold cathode 22 face each other, and the space between the front substrate portion 26 and the electron emitter 25 is supported by the spacer 17. Yes. The light emitting element 20 emits electrons from the cold cathode 22 by the extraction electrode 24, accelerated by the anode electrode 28, and irradiated on the phosphor 27 as the electron beam B (see, for example, Non-Patent Document 2). .)

  As shown in FIG. 3, the four-electrode type light emitting element 30 includes a front substrate portion 39, an electron emitting element 37, and a spacer 38. The front substrate portion 39 includes a phosphor 41, an anode electrode 42, and a substrate 43, and the anode electrode 42 and the phosphor 41 are formed below the substrate 43.

  The electron-emitting device 37 includes a substrate 31, a cold cathode 32, insulating layers 33 and 35, an extraction electrode 34, and a focusing electrode 36. An insulating layer 33 having an opening D is formed on the substrate 31. On the insulating layer 33, an extraction electrode 34, an insulating layer 35, and a focusing electrode 36 are sequentially formed.

  The front substrate portion 39 and the electron-emitting device 37 are disposed so that the phosphor 41 and the cold cathode 32 face each other, and the front substrate portion 39 and the electron-emitting device 37 are supported by a spacer 38. The light emitting element 30 emits electrons by extracting electrons from the cold cathode 32 by the extraction electrode 34, focusing the electron beam B by the focusing electrode 36, and irradiating the phosphor 41 with the electron beam B accelerated by the anode electrode 42. Is.

Thus, by providing the focusing electrode 36 for focusing the electron beam B, the spread of the beam diameter R2 of the electron beam B can be suppressed and color mixing can be prevented. By applying such a light emitting element 30 to a cold cathode display device, it is possible to increase the definition of the display (see, for example, Non-Patent Document 3).
QHWang, et.al., “A nanotube-based field-emission flat panel display”, Applied Physics Letters, pp.2912-2913 (1998) F. Ito, et.al., “Experimentally Low-Voltage Triode Flat Panel Display Using Carbon Nanotube”, Proc. IDW'00, pp. 1177-1178 (2000) YWJin, et.al., “A Study on the Driving Property of DoubleGated Triode-Type Field Emission Display using Carbon Nanotube Emitter”, Proc. IDRC'02, pp. 229-232 (2002)

  However, in the case of the two-electrode type light-emitting element 10, since extraction of electrons and acceleration of extracted electrons are performed by the same electrode 14, it is necessary to drive with a high voltage. For this reason, there are problems that the cost of the drive circuit is increased and the power consumption is increased.

  In the case of the three-electrode type light emitting element 20, it can be driven at a low voltage. However, since electrons emitted from the cold cathode 22 receive a force in the direction of the extraction electrode 24, the beam diameter R 1 of the electron beam B is There has been a problem that the display cannot be made high definition.

  Further, the four-electrode type light emitting element 30 can suppress the spread of the beam diameter R2 of the electron beam B and can be driven at a low voltage. However, there is a problem that the structure is complicated and the manufacturing cost is increased. there were.

  Therefore, the present invention has been made in view of the above-described problems, and relates to an electron-emitting device, a light-emitting device, and a cold cathode display device, and in particular, to achieve a high-definition display by reducing the beam diameter of an electron beam. It is an object to provide an electron-emitting device, a light-emitting element, and a cold-cathode display device that can be manufactured easily by low-voltage driving.

  In order to solve the above-mentioned problems, the present invention is characterized by the following measures.

  According to a first aspect of the present invention, a substrate, an electron emission electrode formed on the substrate and emitting electrons, and formed on the substrate in the vicinity of the electron emission electrode, the electrons are extracted from the electron emission electrode. An extraction electrode; an insulating layer formed on the substrate and having an opening exposing the electron emission electrode and the extraction electrode; and the extracted electron formed on the insulating layer toward the phosphor. This can be solved by an electron-emitting device including a control electrode for control.

  According to the above invention, by providing the extraction electrode in the vicinity of the electron emission electrode formed on the substrate, the distance between the electron emission electrode and the extraction electrode is shortened, and the extraction electrode is low in voltage from the electron emission electrode. You can pull out electrons. Moreover, since the control electrode is an electrode only for controlling the extracted electrons, the electrons can be controlled at a low voltage.

  According to a second aspect of the present invention, the electron emission electrode has an electron emission surface for emitting the electrons, and the electron emission surface is formed of a carbon-based material. This can be solved by the electron-emitting device described in 1).

  According to the above-described invention, the electron emission electrode can emit electrons at a low voltage by forming the electron emission surface using the carbon-based material that easily emits electrons.

  The invention according to claim 3 can be solved by the electron-emitting device according to claim 1 or 2, wherein the extraction electrode has the same structure as the electron-emitting electrode.

  According to the said invention, an extraction electrode can be used as an electron emission electrode by making an extraction electrode the same structure as an electron emission electrode. Thereby, it is possible to reduce the burden on the electron emission electrode by appropriately using the extraction electrode and the electron emission electrode to emit electrons. In addition, since the extraction electrode has the same structure as the electron emission electrode, the extraction electrode and the electron emission electrode can be formed at a time to simplify the manufacturing process.

  According to a fourth aspect of the present invention, an anode electrode provided at a position facing the electron emission electrode and the extraction electrode, a phosphor formed on the surface of the anode electrode, and any one of the first to third aspects. This can be solved by a light-emitting element comprising the electron-emitting element described in 1.

  According to the above invention, the electrons extracted by the control electrode can be accelerated by the anode electrode and guided to the phosphor, and the phosphor can emit light at a low voltage.

  The invention according to claim 5 can be solved by a cold cathode display device comprising a plurality of the light emitting elements according to claim 4.

  According to the above invention, the beam diameter of the electron beam reaching the phosphor can be reduced to increase the definition of the display and can be easily manufactured with low voltage driving.

  As described above, according to the present invention, it is possible to reduce the beam diameter of the electron beam applied to the phosphor to achieve a high-definition display and to be easily manufactured with low voltage drive. An object is to provide an element, a light emitting element, and a cold cathode display device.

  Next, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
First, a cold cathode display device 50 according to a first embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic view of a cold cathode display device according to a first embodiment of the present invention. Note that the X and X directions shown in FIG. 4 indicate the horizontal scanning direction, and the Y and Y directions indicate the vertical scanning direction.

  The cold cathode display device 50 includes a data input terminal 51, a control device 52, a data driver 54, a gate driver 53, and a cold cathode display main body 55. The data input terminal 51 is for supplying image data a which is video data to the control device 52. The control device 52 performs overall control of the cold cathode display device 55, and controls the driving and timing of the data driver 54 by the control signal b, and controls the driving of the gate driver 53 by the control signal c. is there.

  In addition, the control device 52 inputs the image data a input from the data input terminal 51 to the data driver 54. The data driver 54 is for applying a voltage to the control electrode 65 provided in the cold cathode display 55 based on the control signal b. The gate driver 53 is for turning on / off the switch based on the control signal c. As a result, the vertical position at which one horizontal scanning signal is displayed is controlled. The cold cathode display main body 55 is for displaying an image and includes a plurality of light emitting elements.

  Next, the light emitting device 60 of the first embodiment provided in the cold cathode display main body 55 will be described with reference to FIG. FIG. 5 is a schematic view of the light emitting device of the first embodiment. Note that the Z and Z directions shown in FIG. 5 indicate the vertical direction, and the Y and Y directions indicate the vertical scanning direction (the longitudinal direction of the control electrode 65). Further, the “apparatus front side” shown in FIG. 5 indicates a side for viewing an image, and the “apparatus rear side” indicates a side opposite to the apparatus front side.

  The light emitting element 60 includes a front substrate portion 74 provided on the front side of the apparatus, a spacer 68, and an electron emitting element 67 provided on the back side of the apparatus. The electron emission element 67 includes a substrate 61, an electron emission electrode 62, an extraction electrode 63, an insulating layer 64, and a control electrode 65. An insulating layer 64 having an opening E that exposes the substrate 61 is formed on the substrate 61. An electron emission electrode 62 is formed on the substrate 61 in contact with the opening E.

  The electron emission electrode 62 has an electron emission surface 62a, and electrons are emitted from the electron emission surface 62a. As the material of the electron emission surface 62a, a carbon-based material that easily emits electrons, such as graphite, fullerene, carbon nanotube, and amorphous carbon, can be used.

  By forming the electron emission surface 62a using such a carbon-based material, the electron emission electrode 62 can emit electrons at a low voltage. Note that the entire electron emission electrode 62 may be formed of a carbon-based material.

  An extraction electrode 63 is formed on the substrate 61 at a position close to the electron emission electrode 62. In this way, by forming the extraction electrode 63 at a position close to the electron emission electrode 62, the distance between the electron emission electrode 62 and the extraction electrode 63 is shortened. Electrons can be extracted from 62. Further, an electron cloud Q is formed above the electron emission electrode 62 and the extraction electrode 63 by the extracted electrons.

  An insulating layer 64 having an opening E exposing the electron emission electrode 62 and the extraction electrode 63 is formed on the substrate 61. A control electrode 65 is formed on the insulating layer 64 in a direction orthogonal to the electron emission electrode 62 and the extraction electrode 63. The control electrode 65 is for controlling the electrons so as to go to the phosphor 71.

  When a voltage is applied to the control electrode 65, the electron B1 is guided in the direction toward the phosphor 71, and when no voltage is applied, the electron is not guided in the direction toward the phosphor 71. Thus, the control electrode 65 controls whether or not the electrons B1 are directed to the phosphor 71.

  By providing the control electrode 65 that controls only such electrons, the electrons can be controlled at a low voltage. Further, since the control electrode 65 is driven at a low voltage, energy in the Y and Y directions of electrons received from the control electrode 65 is reduced, the spread of the electron beam is suppressed, the beam diameter R3 of the electron beam is reduced, and color mixing is performed. Can be prevented.

  Next, the front substrate part 74 will be described. The front substrate portion 74 includes a substrate 73, an anode electrode 72, and a phosphor 71. On the substrate 73, an anode electrode 72 for accelerating electrons is formed. In addition, a phosphor 71 is formed on the anode electrode 72.

  The front substrate portion 74 and the electron-emitting device 67 are supported by spacers 68 so that the electron-emitting electrode 62 and the extraction electrode 63 and the phosphor 71 face each other. The position where the spacer 68 is provided is not limited to the position shown in FIG.

  Next, a driving method of the light emitting device 60 of the first embodiment will be described with reference to FIGS. FIG. 6 is a diagram schematically showing an equipotential surface formed in the electron-emitting device of the first embodiment. 6 indicates an equipotential surface (hereinafter referred to as equipotential surface S) formed in the light emitting element 60.

  First, in order to extract electrons from the electron emission electrode 62, the potential of the extraction electrode 63 is set to a positive potential with respect to the potential of the electron emission electrode 62, and electrons are extracted from the electron emission surface 62a of the electron emission electrode 62. . Due to the extracted electrons, an electron cloud Q is formed above the electron emission electrode 62 and the extraction electrode 63. At this time, the electrons B <b> 2 receiving a large force in the Y and Y directions are guided to the extraction electrode 63.

  Next, the potential of the control electrode 65 is set to a positive potential with respect to the potential of the electron emission electrode 62. The extracted electrons B1 are guided in the direction of the phosphor 71. At this time, the electrons B1 receive a force in a direction perpendicular to the downwardly projecting equipotential surface S formed in the vicinity of the phosphor 71, and are thus guided in a direction to be focused on the phosphor 71.

  Next, the electron B1 is accelerated by the voltage applied to the anode electrode 71, and the phosphor 71 is irradiated with the electron B1 as a focused electron beam to cause the phosphor 71 to emit light. Further, when it is not desired to cause the phosphor 71 to emit light, the potential of the extraction electrode 63 is lowered to stop the emission of electrons from the electron emission electrode 62 or the potential of the control electrode 65 is lowered to extract the extracted electrons. B1 is prevented from moving in the direction of the phosphor 71.

  Next, an example of a method for manufacturing the electron-emitting device 67 provided in the light-emitting device 60 will be described with reference to FIGS. The front substrate portion 74 has the same configuration as that of the prior art, so the description of the manufacturing method is omitted. 7 to 12 are views showing a manufacturing process of the electron-emitting device. 7 to 12, the same components as those in FIG. 5 are denoted by the same reference numerals.

  First, as shown in FIG. 7, a material to be a member of the extraction electrode 63 is formed on a substrate 61 that has been sufficiently cleaned in advance, and the extraction electrode 63 is formed by a photoetching method, a printing method, or the like. For example, Cu, Al, Ni, Cr, Au, or the like can be used as the material of the extraction electrode 63. The extraction electrode 63 is formed with, for example, a width F of about 10 μm and a height H1 of about 0.1 to 10 μm.

  Next, as shown in FIG. 8, a catalyst layer 75 for forming carbon nanotubes that are the electron emission electrodes 62 is formed. For example, the catalyst layer 75 is formed with a width G of 10 μm and a height H2 of 0.1 to 10 μm. The catalyst layer 75 can be made of Co, Cr, Ni, Fe or the like or an alloy thereof.

  Next, as shown in FIG. 9, an insulating film 64A and a control electrode member 65A are sequentially formed on the structure shown in FIG. The film thickness I of the insulating film 64A is, for example, about 1 to 100 μm. For the insulating film 64A, for example, a SiO 2 film, a SiN film, or the like can be used. The control electrode member 65A may be any material that conducts electricity. For example, Cu, Al, Ni, Cr, Au, or the like can be used. The film thickness J of the control electrode member 65A is, for example, about 0.1 to 10 μm.

  Next, as shown in FIG. 10, a resist film 77 having an opening K is formed on the control electrode member 65A. The opening K has a substantially circular shape, and the diameter thereof is, for example, about 70 μm. Further, the width L shown in FIG. 10 can be formed to about 100 μm.

  Next, as shown in FIG. 11, using the resist film 77 as a mask, the control electrode member 65A and the insulating film 64A are sequentially etched to form the control electrode 65 and the insulating layer 64 having the opening E. To do.

  Next, as shown in FIG. 12, the catalyst layer 75 is chemically reacted using a CVD (Chemical Vapor Deposition) method to form carbon nanotubes that are the electron emission electrodes 62.

  As described above, the electron-emitting device 67 of the light-emitting device 60 can be formed by the manufacturing process as described above. In addition, the light emitting element 60 of the present embodiment is not configured to have the insulating layer 35 and the focusing electrode 36 laminated on the extraction electrode 34 unlike the conventional four-electrode type light emitting element 30. Compared with the case of manufacturing the element 30, it can be manufactured easily. In addition, the manufacturing method of the electron-emitting device 67 of the light emitting device 60 is not limited to the above method.

  Next, a driving method of the cold cathode display main body 55 will be described with reference to FIGS. 13 is a plan view of the back substrate portion of the cold cathode display main body, FIG. 14 is a sectional view of the cold cathode display main body in the G1-G2 direction shown in FIG. 13, and FIG. 15 is a cold cathode display main body. It is the figure which showed the drive pulse waveform in. Note that the X and X directions in FIG. 13 indicate the longitudinal directions of the electron emission electrode 62 and the extraction electrode 63, and the Y and Y directions indicate the longitudinal direction of the control electrode 65.

  In FIG. 15, (a) is the pulse waveform Vp1 supplied to the first extraction electrode 63-1, (b) is the pulse waveform Vp2 supplied to the second extraction electrode 63-2, and (c) is the nth. The pulse waveform Vpn supplied to the extraction electrode 63-n, (d) is the potential Ve supplied to the first to nth electron emission electrodes 62-1 to 62-n, and (e) is the control electrode 65-1 to 65-n. A pulse waveform Vc (pulse waveform corresponding to image data a input from the data input terminal 51) supplied to 65-m is shown. In addition, t1 to tn in FIG. 15 indicate times for scanning one horizontal line (hereinafter, referred to as times t1 to tn), and 1F indicates a time for displaying one screen.

  As shown in FIG. 14, the cold cathode display main body 55 includes a plurality of light emitting elements 60. The cold cathode display main body 55 is provided in the X and X directions in the vicinity of the n electron emitting electrodes 62-1 to 62-n provided in the X and X directions and the electron emitting electrodes 62-1 to 62-n. N extraction electrodes 63-1 to 63-n and n control electrodes 65-1 to 65-n provided in the Y and Y directions. The control electrodes 65-1 to 65 -m are for outputting image signals corresponding to the image data a input from the data input terminal 51, respectively. The electron emission electrodes 62-1 to 62-n and the extraction electrode An image is displayed on the cold cathode display main body 55 by determining which position on the horizontal line the phosphor 71 emits light with 63-1 to 63-m.

  Specifically, as shown in FIG. 15, when the potential Ve of the electron emission electrodes 62-1 to 62-n is used as a reference, the first extraction electrode 63-1, the second extraction electrode 63-2,. ... Electrons are emitted by applying voltages Vp1 to Vpn that are positive potentials to the electron emission electrodes 62-1 to 62-n in the order of the nth extraction electrode 63-n.

  Next, a voltage Vc having a positive potential with respect to the electron emission electrodes 62-1 to 62-n is sequentially applied to the control electrode of the column to be displayed, that is, the column in which electrons are to be guided in the direction of the phosphor. One screen can be displayed on the cathode display main body 55. A moving image is displayed on the cold cathode display main body 55 by repeating such scanning based on the input image data a. In addition, by changing the length of the times tg1 to tgn and driving, it is possible to display an image with changing luminance.

  By configuring the cold cathode display main body 55 with the plurality of light emitting elements 60 in this way, it is possible to drive at a low voltage, prevent color mixing, and increase the definition of the display.

(Second embodiment)
Next, a light emitting device 80 according to a second embodiment of the present invention will be described with reference to FIG. FIG. 16 is a schematic view showing a light emitting device according to the second embodiment of the present invention. In FIG. 16, the same components as those in FIG. The light emitting element 80 includes a front substrate portion 74, an electron emitting element 85, and a spacer 68. Since the front substrate part 74 and the spacer 68 have the same configuration as the light emitting element 60 described above, the description thereof is omitted.

  The electron-emitting device 85 includes a substrate 61, an electron-emitting electrode 82, an extraction electrode 83, an insulating layer 64, and a control electrode 65. An insulating layer 64 having an opening E that exposes the substrate 61 is formed on the substrate 61, and a control electrode 65 is formed on the insulating layer 64.

  An electron emission electrode 82 having an electron emission surface 82 a is formed on the substrate 61 exposed in the opening E, and an extraction electrode 83 is formed on the substrate 61 in the vicinity of the electron emission electrode 82. Yes. The extraction electrode 83 has the same structure as the electron emission electrode 82, and the extraction electrode 83 is formed with an electron emission surface 83a for emitting electrons. As the material of the electron emission surface 83a, a carbon-based material such as graphite, fullerene, carbon nanotube, amorphous carbon, or the like can be used. The electron emission electrode 82 and the extraction electrode 83 are disposed so as to face the phosphor 71.

  In this way, the extraction electrode 83 has the same structure as the electron emission electrode 82 and is formed at a position close to the electron emission electrode 82, so that either the electron emission electrode 82 or the extraction electrode 83 is used as an electrode for emitting electrons. Select to extract electrons at low voltage. In addition, by forming the electron emission surface 83 a using a carbon-based material that easily emits electrons, the electron emission electrode 82 can extract electrons from the extraction electrode 83 at a low voltage. Note that all of the electron emission electrode 82 and the extraction electrode 83 may be formed of a carbon-based material.

  Next, the movement of electrons when electrons are emitted from the electron emission electrode 82 and the movement of electrons when electrons are emitted from the extraction electrode 83 will be described with reference to FIGS. FIG. 17 is a diagram schematically showing the movement of electrons when electrons are emitted from the electron emission electrode, and FIG. 18 is a schematic diagram of the movement of electrons when electrons are emitted from the extraction electrode. It is the figure shown in.

  As shown in FIG. 17, when electrons are emitted from the electron emission electrode 82, electrons are drawn from the electron emission electrode 82 toward the extraction electrode 83, and the electron B <b> 1 is directed toward the phosphor 71 by the control electrode 65. The electrons B1 are accelerated by the anode electrode 72 to become an electron beam and are emitted to the phosphor 71 to emit light. A part of the electrons B <b> 2 having large energy in the Y and Y directions are guided to the extraction electrode 83.

  As shown in FIG. 18, when electrons are emitted from the extraction electrode 83, the electrons B1 are extracted from the extraction electrode 83 toward the electron emission electrode 82, and the electrons B1 are directed toward the phosphor 71 by the control electrode 65. The light is guided and accelerated by the anode electrode 72 to be converted into an electron beam, which emits light by being irradiated onto the phosphor 71 in FIG. A part of the electrons B 2 having large energy in the Y and Y directions are guided to the electron emission electrode 82. Further, switching of the electrodes that emit electrons is performed by inverting the polarity of the voltage applied to the extraction electrode 83 and the electron emission electrode 82.

  Thus, by making the structure of the extraction electrode 83 the same as that of the electron emission electrode 82, it is possible to select either the electron emission electrode 82 or the extraction electrode 83 as an electrode for emitting electrons. Thereby, the electrodes that emit electrons are alternately switched, and the extraction electrode 83 and the electron emission electrode 82 are properly used to reduce the burden on the electron emission electrode 82, prevent the electron emission electrode 82 from being damaged, The lifetime of the emission electrode 82 can be extended.

  In addition, the switching cycle of the electrodes that emit electrons can be performed, for example, for each field (1F), but is not limited thereto. Furthermore, since the extraction electrode 83 has the same structure as the electron emission electrode 82, the electron emission electrode 82, the extraction electrode 83, and the 83 can be formed at a time, and the manufacturing process of the light emitting element 80 can be simplified. it can.

  FIG. 19 is a diagram showing a region where the phosphor of the prior art light-emitting device is irradiated with the electron beam and a region where the phosphor is irradiated with the electron beam of the light-emitting device of the second embodiment. In addition, U shown in FIG. 19 has shown the area | region (henceforth the irradiation area | region U) to which the electron beam of the light emitting element of a prior art was irradiated, and V1, V2 is 2nd Example. The area | region (henceforth irradiation region V1, V2) irradiated with the electron beam of the light emitting element is shown.

  In this embodiment, since the electron emission electrode 82 and the extraction electrode 83 are used as the electrodes for emitting electrons, the phosphor 71 is irradiated with an electron beam on two regions V1 and V2. As shown in FIG. 19, since the total area of the two irradiation regions V1 and V2 is smaller than the area of the conventional electron beam irradiation region U, the electron beam is also focused in the light emitting element 80 of this embodiment. Color mixing can be prevented. In addition, by providing phosphors that emit different colors in the two irradiation regions V1 and V2 of the light emitting element 80, it is possible to further increase the definition of the display.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications, within the scope of the gist of the present invention described in the claims, It can be changed. In addition, it is good also as a structure formed by replacing the position of the electron emission electrode and the position of the extraction electrode. Further, instead of the cold cathode 12 of the light emitting element 10 mentioned in the prior art, an electron emission electrode and an extraction electrode are provided, so that electrons can be extracted by driving at a low voltage.

  The present invention relates to an electron-emitting device, a light-emitting device, and a light-emitting device that can reduce the beam diameter of an electron beam applied to a phosphor to achieve a high-definition display and can be easily manufactured by low-voltage driving. It can be applied to a cold cathode display device.

It is the figure which showed the 2 electrode type light emitting element. It is a diagram showing a three-electrode type light emitting element. It is the figure which showed the 4-electrode type light emitting element provided with the focusing electrode. 1 is a schematic view of a cold cathode display device according to a first embodiment of the present invention. It is the schematic of the light emitting element of 1st Example. It is the figure which showed typically the equipotential surface formed in the light emitting element of 1st Example. It is FIG. (1) which showed the manufacturing process of the electron emission element. It is FIG. (The 2) which showed the manufacturing process of the electron emission element. It is FIG. (The 3) which showed the manufacturing process of the electron emission element. It is FIG. (The 4) which showed the manufacturing process of the electron emission element. It is FIG. (The 5) which showed the manufacturing process of the electron emission element. It is FIG. (The 6) which showed the manufacturing process of the electron emission element. It is a top view of the back substrate part of a cold cathode display main part. It is sectional drawing of the cold cathode display main body of the G1-G2 direction shown in FIG. It is the figure which showed the drive pulse waveform in the cold cathode display main body. It is the figure which showed the outline of the light emitting element of 2nd Example of this invention. It is the figure which showed typically the movement of an electron at the time of discharging | emitting an electron from an electron emission electrode. It is the figure which showed typically the movement of an electron at the time of discharging | emitting an electron from an extraction electrode. It is the figure which showed the area | region where the electron beam of the light emitting element of a prior art was irradiated to the fluorescent substance, and the area | region where the electron beam of the light emitting element of 2nd Example was irradiated to the fluorescent substance.

Explanation of symbols

10, 20, 30, 60, 80 Light-emitting element 11, 15, 21, 29, 31, 43, 61, 73 Substrate 12, 22, 32 Cold cathode 13, 27, 41, 71 Phosphor 14 Electrode 17, 38, 68 Spacers 23, 33, 35, 64 Insulating layers 24, 34, 63, 83 Lead electrodes 25, 37, 67, 70, 85 Electron emitters 26, 39, 74 Front substrate portions 28, 42, 72 Anode electrode 36 Focusing electrode 50 Cold cathode display device 51 Data input terminal 52 Control device 53 Gate driver 54 Data driver 55 Cold cathode display main body 62, 62-1, 62-2, 62-n, 82 Electron emission electrodes 62a, 82a, 83a Electron emission surface 64A Insulation Films 65, 65-1, 65-2, 65-m Control electrode 65A Control electrode member 75 Catalyst layer 77 Resist film a Image data b, c Control signal B Electron beam B1, B2 Electron C, D, E, K Aperture F, G, L Width H1, H2 Height I, J Film thickness Q Electron cloud R1-R5 Beam diameter S Equipotential surface tn Time U, V1, V2 Irradiation area Vc, Vp1, Vp2, Vpn Pulse waveform Ve Potential

Claims (5)

A substrate,
An electron-emitting electrode formed on the substrate and emitting electrons;
An extraction electrode which is formed on the substrate in the vicinity of the electron emission electrode and draws the electrons from the electron emission electrode;
An insulating layer formed on the substrate and having an opening exposing the electron emission electrode and the extraction electrode;
An electron-emitting device, comprising: a control electrode that is formed on the insulating layer and controls the extracted electrons toward the phosphor. The electron emission electrode has an electron emission surface for emitting the electrons,
The electron-emitting device according to claim 1, wherein the electron-emitting surface is made of a carbon-based material.   The electron-emitting device according to claim 1, wherein the extraction electrode has the same structure as the electron-emitting electrode. An anode electrode provided at a position facing the electron emission electrode and the extraction electrode;
A phosphor formed on the surface of the anode electrode;
A light emitting device comprising the electron-emitting device according to claim 1.   A cold cathode display device comprising a plurality of the light emitting elements according to claim 4.

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