Patent Publication Number: US-2012043882-A1

Title: Image display apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image display apparatus including a rear plate having a plurality of electron-emitting devices emitting electrons and a face plate having a plurality of light emitting members emitting light responsive to irradiation with electrons. 
     2. Description of the Related Art 
     Examples of the image display apparatus include an electron beam display apparatus having a plurality of electron-emitting devices emitting electrons and a plurality of light emitting members emitting light responsive to irradiation with electrons from the electron-emitting devices. In particular, an image display apparatus including a plurality of phosphors and a plurality of electron-emitting devices emitting electrons by field emission is expected to have characteristics more excellent than an image display apparatus using other methods. For example, a self-emission type image display apparatus is superior to a recent popular liquid crystal display apparatus in that no backlight is required, the angle of view is wide, fast moving images can be displayed, and the like. 
     The image display apparatus including a plurality of electron-emitting devices has a hermetically sealed container surrounded by a rear plate having a plurality of electron-emitting devices and a face plate having a plurality of light emitting members and anodes with the rear plate spaced from and facing the face plate. The inside of the hermetically sealed container is maintained under vacuum for electron emission. The hermetically sealed container has a spacer interposed between both plates in order to prevent deformation and break of the hermetically sealed container due to the difference in atmospheric pressure between the inside and the outside thereof. 
     Such an image display apparatus is disclosed in Japanese Patent Application Laid-Open No. 2010-067599. The image display apparatus disclosed in Japanese Patent Application Laid-Open No. 2010-067599 includes a plurality of ribs interposed between light emitting members of different light colors on a face plate (light-emitting substrate) to suppress halation. Further, the face plate includes a plurality of anodes (conductors) each covering at least one light emitting member and spaced apart from each other and arranged in matrix; and a plurality of resistance members (power supplying resistors) electrically connecting the plurality of anodes. Each resistance member is located on a rib. Each resistance member has a cover member covering the resistance member and the cover member has a resistance higher than that of the resistance member. Thus, even if a high voltage is applied to between the face plate and the rear plate (electron source substrate), the configuration disclosed in Japanese Patent Application Laid-Open No. 2010-067599 is described to be able to suppress discharge current to achieve high discharge resistance. 
     Unfortunately, in the configuration disclosed in Japanese Patent Application Laid-Open No. 2010-067599, a resistance member as a conductive member exposed from a corresponding cover member and a cover member may be scattered due to electrical load by a voltage for emitting electrons, contacting the spacer between the plates, and physical pressure applied at print process. A conductive member scattered and fallen on an electron-emitting device may cause a short-circuit between a cathode and a gate for applying a predetermined voltage to the electron-emitting device. A short circuit occurring between the cathode and the gate prevents the predetermined voltage from being applied to the electron-emitting device in the short-circuit portion, thus causing a dark point defect in the image display apparatus. Japanese Patent Application Laid-Open No. 2010-067599 does not consider that particle scattering on the face plate side may affect the rear plate side. 
     It is an object of the present invention to provide an image display apparatus capable of suppressing a short-circuit between a cathode and a gate for applying a predetermined voltage to an electron-emitting device. 
     SUMMARY OF THE INVENTION 
     In order to achieve the above object, according to one aspect of the present invention, an image display apparatus comprises; a rear plate provided with a plurality of electron-emitting devices emitting an electron, a face plate arranged in opposition to the rear plate, wherein the face plate is provided with a plurality of light emitting members being arranged within an image display region displaying an image and emitting light responsive to an irradiation with the electron, an anode arranged over the light emitting member, a partitioning member arranged between the light emitting members adjacent to each other and being shaped protruding toward the rear plate beyond the light emitting member, and a first resistance member being arranged on a portion of the partitioning member opposing the rear plate and being electrically connected to the anode, and wherein the image display apparatus further comprises a second resistance member covering the first resistance member so that the first resistance member is not exposed within the image display region, and a volume resistivity of the second resistance member is larger than a volume resistivity of the first resistance member, wherein the partitioning member has a groove formed in the portion of the partitioning member opposing the rear plate, and the second resistance member is formed in the groove  25 . 
     In the present invention, a second resistance member covering a first resistance member at least in an image display region can prevent falling and scattering of a resistance member to suppress a short-circuit between a cathode and a gate for applying a predetermined voltage to the electron-emitting device. Further, a second resistance member covering a first resistance member fallen and scattered on an electron-emitting device does not prevent the possibility of reducing the short-circuit because the second resistance member has a volume resistivity larger than that of the first resistance member. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partially cut-out perspective view of an image display apparatus. 
         FIG. 2  is a plan view of a face plate and a rear plate forming the image display apparatus. 
         FIG. 3  is a sectional view of an image display apparatus according to a first example along line A-A′ of  FIG. 1 . 
         FIG. 4  is a sectional view of the same image display apparatus as illustrated in  FIG. 3 , along line B-B′ of  FIG. 1 . 
         FIG. 5  is a sectional view of an image display apparatus according to another example along line A-A′ of  FIG. 1 . 
         FIG. 6  is a sectional view of the same image display apparatus as illustrated in  FIG. 5 , along line B-B′ of  FIG. 1 . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Preferred embodiments of the present invention will now be described in detail in accordance with the accompanying drawings. 
     The image display apparatus of the present invention can be applied to an image display apparatus including a plurality of electron-emitting devices emitting electrons and a plurality of light emitting members emitting light responsive to irradiation with electrons, for example, to a field emission display (FED) and a cathode-ray tube (CRT). Particularly, in the FED, an intense electric field occurs between the anode and the cathode, and a local high load is applied to a contact portion between the face plate and the rear plate and the spacer supporting the plates, thus increasing the possibility of scattering of a conductive member disposed in the face plate. Thus, the image display apparatus of the present invention can be applied to the FED. 
     Now, by taking an example of an FED, embodiments of the present invention will be described in detail using the accompanying drawings. 
       FIG. 1  illustrates an outline of an image display apparatus  100  of the present embodiment.  FIG. 1  is a partially cut-out perspective view of the image display apparatus  100  in order to illustrate the internal structure thereof.  FIG. 2  is a schematic view of a face plate  11  viewed from a rear plate  12  forming the image display apparatus  100  together with the face plate  11 .  FIG. 2  is a schematic view of the rear plate  12  viewed from the face plate  11 .  FIG. 3  is a sectional view along line A-A′ of  FIG. 1 .  FIG. 4  is a sectional view along line B-B′ of  FIG. 1 . Note that to clarify the positions of the line A-A′ and the line B-B′ in  FIG. 1 , the line A-A′ and the line B-B′ are also illustrated in the respective positions in  FIG. 2 . 
     The rear plate  12  has a substrate and a plurality of electron-emitting devices  16  mounted on the substrate. In the present embodiment, as illustrated in  FIG. 2 , the plurality of electron-emitting devices  16  are arranged in a grid pattern. The plurality of electron-emitting devices  16  each are arranged in a matrix connected to a scanning wiring  14  as a cathode line and an information wiring  15  as a gate line. 
     The face plate  11  includes; a substrate, a plurality of light emitting members  17  mounted on the substrate and emitting light responsive to irradiation with electrons emitted from the plurality of electron-emitting devices  16 , and a plurality of anodes  20  mounted on the plurality of light emitting members  17 . The face plate  11  is spaced from and facing the rear plate  12 . The plurality of light emitting members  17  are spaced from and facing the plurality of electron-emitting devices  16  in an image display region for displaying an image. Further, the face plate  11  has a plurality of partitioning members  19  each interposed between the mutually adjacent light emitting members  17  and protruding further than the light emitting members  17  toward the rear plate side. In the present embodiment, the plurality of partitioning members  19  are linearly arranged in a stripe form to partition the plurality of light emitting members  17  arranged in a grid pattern into a plurality of groups. 
     The portion of a top portion  24  of a partitioning member  19  facing the rear plate  12  has a first resistance member  21  electrically connected to an anode  20 . In the present embodiment, a plurality of the first resistance members  21  are arranged in a stripe form electrically connecting the mutually adjacent anodes  20  in a Y direction in the drawing to each other. The first resistance members electrically connect a feeding electrode  22  located outside the image display region and the anodes  20  inside the image display region. A voltage can be applied to the anodes  20  from an external power supply to apply an intense electric field to between both plates  11  and  12 . 
     The partitioning members  19  partitioning the light emitting members  17  prevent electrons hitting an anode  20  on a light emitting member  17  from scattering and hitting another light emitting member  17  again (halation). 
     As illustrated in  FIGS. 1 and 3 , a spacer  13  as an atmospheric-pressure-resistant support structure is interposed between the rear plate  12  and the face plate  11 . The spacer  13  is arranged in a portion between the mutually adjacent light emitting members  17  so as not to affect the image displayed on the image display apparatus  100 . In the present embodiment, the spacer  13  linearly extends in the X direction in the drawing. 
     Meanwhile, each first resistance member  21  is located at the top portion  24  of the partitioning member  19  and arranged along the partitioning members  19  so as to cross the spacer  13 .  FIGS. 2 and 3  illustrate a plurality of second resistance members  23  each covering a first resistance member  21  and having a volume resistivity larger than that of the first resistance member  21  so as not to expose the first resistance member  21  at least in the image display. Thus, in the crossing portion between the spacer and the partitioning member  19 , the spacer (third resistance member)  13  mutually contacts the second resistance member  23 . 
     If there is no second resistance member  23 , in the crossing portion between the spacer  13  and the partitioning member  19 , the spacer  13  mutually contacts the first resistance member  21 . In this case, an external impact causes the crossing portion to receive not only atmospheric pressure but also a shearing force due to rubbing between the spacer  13  and the first resistance member  21 . Thereby, a part of the first resistance member  21  may be scattered into particles. Further, the first resistance member  21  may be scattered by electrical load due to a voltage applied to emit electrons. The first resistance member  21  can have a volume resistivity of 0.01 to 10 (Ω·m). A part of the first resistance member  21  scattered and fallen on an electron-emitting device  16  mounted on the rear plate  12  may cause a short-circuit between the cathode and the gate. 
     In the present embodiment, as described hereinbefore, the second resistance members  23  at least in the image display region cover all the first resistance members  21 , and the spacer  13  contacts the second resistance members  23 , thereby suppressing falling and scattering of the first resistance members  21 . Further, a second resistance member  23  fallen and scattered on an electron-emitting device  16  does not prevent the effect of suppressing the possibility of causing short circuit between the cathode and the gate because the second resistance member  23  has a volume resistivity larger than that of the first resistance member  21  and has an insulating property. In order to exert the effect, the second resistance members  23  need to have a volume resistivity large enough to prevent electrical short circuit from occurring even if a second resistance member  23  falls and scatters on an electron-emitting device  16  on the rear plate  12 . More specifically, each second resistance member  23  can have a volume resistivity of 1 M (Ω·m) or more. 
     Note that the second resistance members  23  may cover not only the first resistance members  21  inside the image display region but also the first resistance members  21  outside the image display region, and may cover at least part of the feeding electrode  22 . 
     Further, the second resistance members  23  can have a structure containing a void. Thus, when a second resistance member  23  contacts the spacer  13 , the structure can absorb the pressure from the spacer  13  to relax local stress concentration in the crossing portion between the second resistance member  23  and the spacer  13 . Particularly, when the plurality of partitioning members  19  vary in height, the stress is focused on a second resistance member  23  on a higher partitioning member  19  or the spacer  13  contacting the second resistance member  23 . Even in that case, the structure can prevent deformation and break of the spacer  13  and the partitioning member  19 . 
       FIGS. 5 and 6  illustrate an image display apparatus according to another example of the present invention.  FIG. 5  is a sectional view along line A-A′ of  FIG. 1 .  FIG. 6  is a sectional view along line B-B′ of  FIG. 1 . The present embodiment in  FIGS. 5 and 6  differ in the shape of the partitioning member  19  from the first embodiment in  FIGS. 3 and 4  respectively. The surface of the partitioning member  19  facing the rear plate  12  includes a groove  25  along the partitioning member  19 . The first resistance member  21  is disposed in the groove  25 . The structure can suppress deformation of the first resistance member  21  due to a pressure from the spacer  13 , can prevent disconnection of the first resistance member  21 , and can prevent image display defects such as a line defect. 
     Now, specific examples of each component member will be described in detail. The material of the substrate forming the face plate  11  for use in the present invention is not particularly limited, but may include commonly used soda-lime glass, annealed soda-lime glass or high strain point glass. 
     The face plate  11  has a light blocking member  18  located on a surface of the substrate. Examples of the light blocking member  18  may include a well-known black matrix structure such as for use in a CRT. The material of the light blocking member  18  may generally include black metal, black metal oxide, or carbon. Examples of the black metal oxide may include ruthenium oxide, chromic oxide, iron oxide, nickel oxide, molybdenum oxide, cobalt oxide and copper oxide. 
     The material of the partitioning member  19  may include an inorganic mixture having a volume resistivity near that of an insulator such as a glass material containing metal oxide such as lead oxide, zinc oxide, bismuth oxide, boron oxide, aluminum oxide, silicon oxide and titanium oxide. The patterning method of the partitioning member  19  may include a sandblasting method, a photosensitive paste applying method and an etching method. Note that the height of the partitioning member  19  may be appropriately set according to the specifications of the image display apparatus  100 . 
     Further, the photosensitive paste applying method may be used to form a groove  25  along the partitioning member  19  on a surface of the partitioning member  19  facing the rear plate  12 . In order to form the groove  25 , a mask portion with a width of 5 to 20 μm needs to be formed in a photomask for use in patterning so as to allow the groove forming portion to be unexposed. The use of the photomask to expose the photosensitive paste formed as the partitioning member  19  allows an unexposed portion to be formed on the surface of the partitioning member  19  and the inside portion thereof to be exposed. Then, the unexposed portion can be subjected to development to form the groove  25 . 
     The material of the light emitting member  17  may include a phosphor crystal emitting light using an electron beam as the excitation source. Specific materials of the phosphor may include a phosphor material for use in a CRT as described in the “Phosphor Handbook” compiled by Keikoutaidougakukai (Phosphor Research Society) and published by Ohmsha Ltd. A phosphor-dispersed paste can be coated, dried, and baked to be used as the light emitting member  17 . Subsequently, a solution containing alkali-silicate, namely, a so-called water glass is sprayed and coated on the substrate in a uniform manner as a binding member, and then dried to bond the light emitting member  17  to the substrate. 
     Examples of the anode  20  may include a metal back made of Al, known for use in a CRT. The patterning method of the anode  20  may include a vapor deposition method through a mask and an etching method. 
     Examples of the first resistance member  21  may include a resistor comprising a mixture between conductive particles such as ATO-coated titanium oxide particles and glass materials containing metal oxide such as lead oxide, zinc oxide, bismuth oxide, boron oxide, aluminum oxide, silicon oxide and titanium oxide. The first resistance members  21  can have a resistance value of 1 kΩ to 1 MΩ between the mutually adjacent light emitting members  17  (anodes  20 ) along the Y direction in the drawing. Further, the patterning of the first resistance members  21  may include any method such as a printing method and a coating method by means of a dispenser. 
     The material of the feeding electrode  22  is not particularly limited as long as the material is conductive such as metal. The resistance value between both ends of the feeding electrode  22  can be 0Ω to 1 kΩ. 
     The material of the second resistance member  23  may include a mixture of a glass material with metal oxide such as zinc oxide, tin oxide and titanium oxide. The second resistance member  23  can have a volume resistivity of 1 (M Ωm) to 100 (M Ωm). 
     In order to relax an external force to the second resistance member  23  from the spacer  13 , the second resistance member  23  should to have an appropriate flexibility. The flexibility can be achieved by reducing glass content percentage. The flexibility may be achieved in such a manner that a coating paste composition as a precursor of the second resistance member  23  is impregnated with resin particles and the precursor is baked to form a void inside the second resistance member  23 . In this case, a less brittle second resistance member  23  can be formed. 
     Now, the rear plate  12  will be described.  FIGS. 1 and 2  illustrate a plurality of electron-emitting devices  16  mounted on an inner surface of the rear plate  12  so as to emit electrons for exciting a plurality of light emitting members  17  to emit light. Suitable examples of the electron-emitting device  16  may include a surface-conduction electron-emitting device.  FIGS. 1 and 2  further illustrate a plurality of scanning wirings  14  and a plurality of information wirings  15  mounted on the inner surface of the rear plate  12  so as to supply a drive voltage to each electron-emitting device  16 . 
     The material of the spacer  13  is desirable to conduct a very small amount of current for antistatic purposes and may include a mixture of a conductive member with an insulating material such as glass. The resistance value of the spacer per abutting portion between the spacer  13  and the first resistance member  21  is desirable to be 10 10  to 10 14 Ω. Further, in order to control the potential of the spacer  13 , the resistance value in the height direction of the spacer  13 , namely, in a direction of the face plate  11  facing the rear plate  12  needs to be set higher than the resistance value of the second resistance member  23  in the same direction. Further, the surface of the spacer  13  may be covered with a resistance member. 
     The image display apparatus  100  is configured such that the spacer  13  is interposed between the face plate  11  and the rear plate  12  as described above and the edge portions of the face plate  11  and the rear plate  12  are bonded through a side wall  24  to form a hermetically sealed container. 
     The above embodiment has the spacer  13  interposed between the face plate  11  and the rear plate  12 , but the spacer  13  may not be required as long as the hermetically sealed container has a strength enough to withstand the atmospheric pressure. Even in the above configuration, the second resistance member  23  can prevent scattering of the first resistance member  21  caused by an intense electric field occurring at least between both places  11  and  12 . 
     FIRST EXAMPLE 
     Now, a first example of the present invention will be described.  FIG. 3  is a sectional view along line A-A′ of  FIG. 1 .  FIG. 4  is a sectional view along line B-B′ of  FIG. 2 . The face plate  11  used for the present example was formed in the following steps. 
     (Step 1: Light Blocking Member Formation) 
     A black paste (NP-7811M1 manufactured by Noritake Kizai Co., Ltd.,) was printed on an entire surface of a cleaned glass substrate. Subsequently, the black paste was dried at 150° C., exposed to 1000 mJ/cm 2 , developed, and then baked at 580° C. to form a plurality of light blocking members  18  each having an opening portion with a horizontal pitch of 210 μm and a vertical pitch of 630 μm, the opening portion having a size of 150×200 μm and a thickness of 5 μm. 
     (Step 2: Partitioning Member Formation) 
     Next, in order to form a partitioning member  19 , an insulating paste containing alumina particles with an average particle diameter of about 5 μm added to a borosilicate glass was applied along the center line of the light blocking members  18  with a pixel interval pitch (210 μm) by means of a slit coater. Subsequently, the insulating paste was dried at 95° C., exposed to 300 mJ/cm 2 , developed, and then baked at 580° to form a plurality of stripe-shaped partitioning members  19  each with a thickness of 200 μm and a width of 55 μm. 
     (Step 3: Light Emitting Member Formation) 
     Next, as a light emitting member  17 , a paste containing dispersed P22 phosphors for use in a CRT field was used to pour and print the phosphors by screen printing according to the stripe-shaped partitioning members  19 . In the present example, three color RGB phosphors were applied differently for each stripe so as to make a color display. Each phosphor had a film thickness of 5 μm. Subsequently, the three color phosphors were dried at 110° C. Note that the drying may be performed separately for each color or collectively for all three colors. Further, after being baked at 500°, a water solution containing alkali-silicates acting later as a binding member, namely, a so-called water glass, was sprayed and applied to the phosphors. 
     (Step 4: Anode Formation) 
     Next, ethyl cellulose was applied by printing and dried, a space between phosphor powder particles was filled with ethyl cellulose resin, and then an aluminum film was deposited on the phosphors to form anodes  20 . In this case, a dry film resist was laminated only on a portion corresponding to a part of the phosphors as the light emitting members  17  and the stripe-shaped partitioning members  19  to pattern the anodes  20 . Note that the aluminum film of the anodes  20  had a thickness of 100 nm. 
     (Step 5: First Resistance Member Formation) 
     Next, a plurality of first resistance members  21  were formed in such a manner that a conductive glass paste with a volume resistivity of 0.5 (Ωm) (NP-7840J manufactured by Noritake Kizai Co., Ltd.,) was printed on the top portions  24  of the partitioning members  19  by a pattern printing plate, dried at 110° C., and baked to form the first resistance members  21  with a width of 10 μm. Note that when the material used as the first resistance members  21  was applied to a test pattern and the resistance value was measured, the sheet resistance was 50 kΩ/sq. 
     (Step 6: Second Resistance Member Formation) 
     In order to find the conditions for creating a material with a desired volume resistivity, the following work was performed. First, zinc oxide and glass frit were mixed to form a paste. Then, the paste was applied on a test pattern, dried at 110° C., and baked at 500° C., and then the volume resistivity was measured by means of a product name: Hiresta-UP-MCP-HT450 (manufactured by Mitsubishi Chemical Analytech Co., Ltd.). The mixing ratio between the zinc oxide and the glass frit was changed until a volume resistivity of  1  M (Ωm) was obtained. 
     Next, a plurality of second resistance members  23  were formed in such a manner that a paste having a predetermined mixing ratio was printed on the partitioning members  19  so as to cover the entire first resistance members  21 , dried at 110° C., and baked at 500° C. so that the total thickness of the first resistance members  21  and the second resistance members  23  was 20 μm. Thus, the face plate  11  was formed. 
     In order to verify the volume resistivity of the second resistance members  23 , a sample for measuring the volume resistivity was formed under the same conditions. The formed second resistance members  23  were removed from the face plate  11 , and crushed, and then the volume resistivity was measured by means of a powder resistivity meter (product name: MCP-PD51 manufactured by Mitsubishi Chemical Analytech Co., Ltd.). As a result, the volume resistivity of the second resistance members  23  was 1 M (Ωm). 
     (Step 7: Image Display Apparatus Formation) 
     The image display apparatus  100  illustrated in  FIG. 1  was formed such that the spacer  13  was interposed between the face plate  11  and the rear plate  12  as described above and a peripheral portion was hermetically sealed into the edge portions of the face plate  11  and the rear plate  12  through the side wall  24 . As illustrated in  FIG. 3 , the spacer  13  abutted against the second resistance members  23  on the partitioning members  19 . 
     The spacer  13  is desirable to be a high resistance member (third resistance member) conducting a very small amount of current for antistatic purposes. Further, since the spacer  13  abuts against the second resistance members  23 , the resistance value in the height direction (Z direction) of the spacer  13  needs to be higher than the resistance value in the film thickness direction (Z direction) of the second resistance members  23 . Thus, the spacer  13  can be controlled to a desired potential. 
     In the present example, the resistance value per abutting portion between the spacer  13  and the second resistance members  23  was such that the spacer  13  was 10 10 Ω, and the second resistance members  23  were 4×10 9 Ω. 
     (Evaluation of Image Display Apparatus) 
     As thus formed, an image was displayed on the image display apparatus  100  by applying a voltage of 10 kV to the anodes  20  through the feeding electrode  22 . As a result, a sufficient luminance intensity was obtained and an excellent image was displayed free from a dark point defect caused by a short-circuit between the cathode and the gate. There was no abnormal discharging due to spacer charging. 
     SECOND EXAMPLE 
     Now, a second example of the present invention will be described.  FIG. 5  is a sectional view along line A-A′ of  FIG. 1 .  FIG. 6  is a sectional view along line B-B′ of  FIG. 2 . The second example differs from the first example in that the partitioning members  19  have a groove  25  and the groove  25  includes the first resistance members  21  in side thereof. 
     The steps 1 and 3 to 7 are the same as those in the first example. Thus, the following description will focus on the step 2 different from that in the first example. 
     (Step 2: Partitioning Member Formation) 
     First, an insulating paste containing alumina particles with an average particle diameter of about 5 μm added to a borosilicate glass was applied in a stripe form along the center line of the light blocking members  18  with a pixel interval pitch (210 μm) by means of a slit coater, and dried at 95° C. Then, the insulating paste was exposed to 300 mJ/cm 2  using a photomask including stripe-shaped portions each with a line width of 15 μm along the center of each partitioning member  19 . Subsequently, the insulating paste was developed and baked at 580° C. to form stripe-shaped partitioning members  19  with a thickness of 200 μm and a width of 55 μm containing a groove  25  with a width of 30 μm and a depth of 20 μm. 
     In the above steps, the image display apparatus  100  including the face plate  11  illustrated in  FIG. 5  was formed. 
     (Evaluation of Image Display Apparatus) 
     The same evaluation as in the first example was performed in the present example. As a result, the similar results to that in the first example were obtained. 
     FIRST COMPARATIVE EXAMPLE 
     Now, a first comparative example of the present invention will be described. The first comparative example differs from the first example in that the second resistance members  23  had a volume resistivity of 100 k (Ωm). In order to form such a member, the content percentage of the glass frit contained in the second resistance members  23  described in the first example was reduced. The image display apparatus was formed under the same conditions as in the first example except the above. 
     (Evaluation of Image Display Apparatus) 
     As thus described, ten image display apparatuses were formed and an image was displayed for evaluation by applying a voltage of 10 kV to the anodes  20  through the feeding electrode  22  in the same manner as in the first example. As a result, each of the nine image display apparatuses provided sufficient luminance intensity and displayed an excellent image free from a dark point defect caused by a short-circuit between the cathode and the gate, and one image display apparatus had a dark point defect caused by a short-circuit between the cathode and the gate. 
     In contrast to this, in the configuration of the first example, all the 20 image display apparatuses displayed an excellent image free from a dark point defect caused by a short-circuit between the cathode and the gate. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2010-182286, filed Aug. 17, 2010, which is hereby incorporated by reference herein in its entirety.