1. Field of the Invention
The present invention relates to a display panel and an image display apparatus provided with a flat, rectangular vacuum vessel.
2. Description of the Related Art
Image display apparatuses such as a field emission display (FED) are known that are of a type in which electrons emitted from electron-emitting devices are radiated onto a light emitter such as a phosphor. Such image display apparatuses use a display panel provided with a flat, rectangular vacuum vessel in which the interior thereof is maintained at a pressure lower than atmospheric pressure (vacuum). In order to maintain the internal space in a vacuum, a plurality of spacers are typically provided within the flat, rectangular vacuum vessel.
In an image display apparatus having a display panel provided with a flat, rectangular vacuum vessel in this manner, it is required to prevent the vacuum vessel from being damaged by impacts applied to the image display apparatus. In addition, it is also required to not only prevent damage to the exterior of the vacuum vessel, but also to prevent damage to members relating to image display located within the vacuum vessel. Examples of impacts that cause damage to the vacuum vessel include impacts to the image display apparatus from the outside, impacts occurring during transport or installation, and impacts caused by dropping due to careless handling.
Japanese Patent Application Laid-open No. 2005-011764 discloses a reinforcement frame attached to the back (side on the opposite side from the display side) of a vacuum vessel that composes a display panel in order to improve the mechanical strength of the vacuum vessel. In addition, Japanese Patent Application Laid-open No. 2005-227766 discloses the adhesion of a reinforcement frame to a vacuum vessel with a plurality of adhesives. Japanese Patent Application Laid-open No. 2006-185723 discloses a vacuum vessel provided with long, narrow plate-like spacers arranged so that each of the lengthwise directions thereof are parallel. A mode is disclosed therein in which long, narrow plate-like spacers are contacted in a plurality of spacer contact layers intermittently provided on a metal back layer that covers a light-emitting surface. In addition, Japanese Patent Application Laid-open No. H10-326580 discloses the providing of a protective plate on a display surface of a vacuum vessel that composes a display panel.
In Japanese Patent Application Laid-open No. 2005-227766, adhesive is also provided in a direction perpendicular to the lengthwise direction of the plate-like spacers. Consequently, dropping impacts and the like lead to damage to the plate-like spacers and contact members in contact with the plate-like spacers, and this may cause deterioration of display images. In addition, in Japanese Patent Application Laid-open No. 2005-227766, adhesive is provided to the edges of the vacuum vessel. Consequently, impacts are applied to the vacuum vessel through the reinforcement frame during transport or caused by dropping and the like, and impacts are transmitted directly to the edges in which bending occurs, thereby leading to damage to the edges. In addition, when adhering the reinforcement frame to the edges in which bending occurs, variations in the thickness of the adhesive or pressing force applied during adhesion and the like can also lead to damage to the edges.
The present invention provides an image display apparatus capable of inhibiting damage to plate-like spacers, contact members contacted by the plate-like spacers, and the edges of a vacuum vessel.
The present invention in its first aspect provides a display panel including: a vacuum vessel provided with a face plate, a rear plate having a surface that opposes the face plate at an interval therefrom, a connecting member that surrounds a space between the face plate and the rear plate, is provided between the face plate and the rear plate and connects the face plate and the rear plate, and a plurality of plate-like spacers provided between the face plate and the rear plate so that the lengthwise directions thereof are parallel to each other, and a fixing member adhered to the vacuum vessel by a plurality of linear bonding members provided on a surface of the rear plate on the opposite side from the surface opposing the face plate, wherein each of the plurality of linear bonding members is provided to the rear plate at mutually prescribed intervals and along the lengthwise direction of the plurality of spacers, and the plurality of linear bonding members are provided only in a portion of a region on the surface of the rear plate on the opposite side from the surface opposing the face plate, the portion of the region being located on the opposite side from the region surrounded by the connecting member on the surface of the rear plate that opposes the face plate.
The present invention in its second aspect provides an image display apparatus including: the display panel; and a supporting member that supports the vacuum vessel composing the display panel, by means of the fixing members.
According to the present invention, an image display apparatus can be provided that is capable of inhibiting damage to plate-like spacers, contact members contacted by the plate-like spacers, and the edges of a vacuum vessel. In addition, a display panel and image display apparatus can be provided that are capable of realizing reduced thickness, light weight and low costs.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
The following provides an explanation of embodiments of the present invention. The present invention is effective for use in a display panel provided with a flat, rectangular vacuum vessel 10 as shown in
A display panel refers to a so-called display module, and is at least provided with the vacuum vessel 10, fixing members for fixing the vacuum vessel 10 to a supporting member, and bonding members that adhere the fixing members to the vacuum vessel. Moreover, the display panel is also typically provided with a drive circuit within the vacuum vessel for driving an electron-emitting device and an anode electrode. On the other hand, an image display apparatus refers to an apparatus that is at least provided with a supporting member for placing the display panel on an installation surface in addition to the display panel. Moreover, an image display apparatus also refers to an apparatus provided with a receiver for receiving television signals, an image processing circuit for carrying out a prescribed processing according to input image signals and characteristics of the display panel, and speakers and the like as necessary.
An explanation is first provided of a display panel to which the present invention is preferably applied using
Furthermore, the connecting member 28 is provided at a prescribed distance away from each periphery of the face plate 11 and the rear plate 12 so as to be located farther to the inside than each periphery. Consequently, a space (internal space) maintained in vacuum, the connecting member 28 that surrounds the space maintained in a vacuum, and a space (external space) at atmospheric pressure that surrounds the connecting member are present between the face plate 11 and the rear plate 12. Therefore, the vacuum vessel 10 is provided with an edge portion for surrounding the connecting member 28. In other words, the connecting member 28 is present between the internal space 29 of the vacuum vessel 10 and the edge portion of the vacuum vessel 10. The edge portion of the vacuum vessel 10 is composed of an edge portion of the rear plate 12 located to the outside of the region of the rear plate 12 adhered to the connecting member 28, and an edge portion of the face plate 11 located to the outside of the region of the face plate 11 adhered to the connecting member 28. In general, the surface area of the edge portion of the rear plate 12 is larger than that of the edge portion of the face plate 11 in order to connect the wiring of the electron-emitting device and the drive circuit. When forming (connecting) the vacuum vessel 10, one of the plates is pressed against the other plate while at least heating the connecting member 28 and the connecting portion between the rear plate 12 and the face plate 11. Consequently, bending occurs in the edge portions of each of the rear plate 12 and the face plate 11 after they have been connected due to unavoidable thermal stress when connecting, variations in the height of the bonding members 23 and the like. Since the surface area of the edge portion of the rear plate 12 is larger than the surface area of the edge portion of the face plate 11 as previously described, the edge portion of the rear plate 12 bends more than the edge portion of the face plate 11. This type of phenomenon is frequently observed in the case of employing a method for forming the vacuum vessel as previously described.
On the other hand, as shown in
A large number of electron-emitting devices 18 that respectively emit an electron beam are provided on the surface of the rear plate 12 that opposes the face plate (the surface on the side of the internal space) as electron sources that excite the R, G and B light emitters of the light emitter layer 15. These electron-emitting devices 18 are arranged in the form of a matrix corresponding to pixels (light emitters R, G and B). Furthermore, surface conduction electron-emitting devices or field emission electron-emitting devices can be applied for the electron-emitting devices 18. A large number of wires 21 that drive the electron-emitting devices 18 are provided in the form of a matrix on the surface of the rear plate 12 on the side of the internal space, and the ends thereof are led outside the vacuum vessel 10 (see
A large number of long, narrow plate-like spacers 14 are arranged between the rear plate 12 and the face plate 11 in order to support atmospheric pressure that acts on these plates and maintain the space between the rear plate 12 and the face plate 11 (internal space 29) at a prescribed interval. In the case of defining the lengthwise direction (direction of the long side) of the face plate 11 and the rear plate 12 as a first direction X, and defining the direction perpendicular thereto (direction of width or direction of the short side) as a second direction Y, the plate-like spacers 14 extend in the first direction X. In other words, the lengthwise direction 110 of the plate-like spacers 14 is the first direction X. The large number of plate-like spacers 14 are arranged at a prescribed interval in the second direction Y. The interval in the second direction Y can be, for example, 1 to 50 mm. The spacers 14 can be composed of a long, narrow glass plates or ceramic plates. In addition, a high resistance film may be arranged on the surface of the plates or surface irregularities may be provided in the plates as necessary. The height of the spacers 14 (length in the Z direction) is several times to ten or more times the width thereof (length in the second direction Y), and the length thereof (length in the first direction X) is several tens of times to several hundreds of times the height.
In a display panel and image display apparatus provided with the above-mentioned vacuum vessel, in the case of display an image, an anode voltage is applied to the R, G and B emitter layers through the metal back layer 20. In addition, electron beams emitted from the electron-emitting devices 18 are simultaneously accelerated by the anode voltage and made to collide with the light emitters. As a result, the corresponding R, G and B light emitters are excited and emit light to display a color image.
As shown in
Next, an explanation is provided of an example of an image display apparatus to which the present invention is preferably applied using the schematic diagrams shown in
A fixing member 103 for fixing the vacuum vessel 10 to a rigid body in the form of a supporting member 108 is provided on the back of the vacuum vessel 10. Furthermore, the supporting member 108 can removably fix a display panel at least provided with the fixing member 103 and bonding members 122 in addition to the vacuum vessel 10. The bonding members 122 for adhering the fixing member 103 to the vacuum vessel 10 are provided on the back of the rear plate 12 of the vacuum vessel 10 (side on the opposite side from the face plate 11) as explained using
Although printed circuit boards for driving the display panel are normally provided on the back side of the display panel (opposite side from the rear plate 12), the various types of printed circuit boards are omitted from
Next, an explanation of the locations at which the bonding members 122 are arranged with respect to the vacuum vessel 10 is provided using
As shown in
In addition, the bonding members 122 are provided only in a region located on the opposite side of a portion of the region on the side of the rear plate 12 that opposes the face plate 11, the portion of the region being surrounded by the connecting member 28 (region located in the internal space 29 of the vacuum vessel 10). Namely, when the side of the rear plate 12 that opposes the face plate 11 is defined as a first main side, and the side of the rear plate 12 on the opposite side from the first main side is defined as a second main side of the rear plate 12, then the bonding members 122 are provided only in a portion of the region of the second main side. A region that is a portion of the second main side refers to a region on the opposite side from the region of the first main side surrounded by the connecting member 28 (region located in the internal space of the vacuum vessel 10). In other words, a region that is a portion of the second main side refers to a region directly behind the region of the first main side surrounded by the connecting member 28 (region located in the internal space of the vacuum vessel 10). As a result of configuring in this manner, the bonding members 122 are not provided at the previously described edge portions of the vacuum vessel 10 where bending is large. Consequently, even if an impact is applied to the vacuum vessel 10 from the supporting member 108 through the fixing member 103 and the bonding members 122, damage to the edge portions of the vacuum vessel 10 can be avoided. In addition, since a load is not applied to the edge portions of the vacuum vessel 10 even when the fixing member 103 is adhered to the vacuum vessel 10, the number of opportunities for damage to the edge portions of the vacuum vessel 10 can be decreased. In addition, since the region where the bonding members 122 are provided is a comparatively flat surface as explained using
Double-sided adhesive tape or adhesive and the like can be used for the bonding members 122. The material, shape, thickness, surface area and the like of the bonding members 122 are suitably set in consideration of the strength, impact absorption and thermal conductivity of the bonding members 122 and flatness of the supporting member and so forth. A silicone-based, elastic resin adhesive, for example, can be used as an adhesive, while double-sided adhesive tape having an acrylic base can be used as double-sided adhesive tape. A silicone-based elastic resin adhesive in the form of TSE3944 (Momentive Performance Materials Japan LLC), for example, can be used for the silicone-based elastic resin adhesive. The creep property of the bonding members 122 is generally expressed as γc=A×τ×t0.5 (where, γc: shear creep strain, τ: shear stress [Pa], t: time [sec]), and the value of A is preferably 1.0×10−9 or less. If the amount of creep is excessively large, the vacuum vessel 10 ends up lowering from its initial fixed location over time, which is undesirable in terms of appearance. Providing the bonding members 122 with the creep property as described above prevents the vacuum vessel 10 from lowering from its initial fixed location over a long period of time even if the surface area of the bonding members 122 decreases considerably (such as to one-tenth or less the display surface area). Thus, the amount of adhesive used can be decreased considerably making it possible to realize an adhesive structure at low cost.
The plurality of bonding members 122 are arranged so as to satisfy linear symmetry by having a center line 144 in the horizontal direction of the image display region (or the rear plate 12) as the axis of symmetry thereof (see
The fixing member 103 can be composed of, a metal plate made of aluminum, iron or magnesium. Although the fixing member 103 is composed of a metal plate provided with a surface area roughly equal to that of the rear plate 12 in
The fixing member can also be composed with a plurality of fixing members 103 as shown in
Since the strength of the fixing members per se decreases in the case of using a plurality of fixing members 103 as shown in
The following provides an explanation of a more detailed structure when using the plurality of fixing members 103 using
The plurality of fixing members 103 for fixing the vacuum vessel 10 to a rigid body in the form of the supporting member 108 are adhered to the back side of the rear plate 12 (side on the opposite side from the side (inside) that opposes the faceplate 11) using the bonding members 122. In this manner, the vacuum vessel 10 can be supported by the supporting member 108 through the plurality of fixing members 103. In addition, the arrows 110 in
In addition, the front plate 102 is adhered by a bonding member 121 to the surface of the front side of the face plate 11 of the vacuum vessel 10 (side on the opposite side from the side that opposes the rear plate 12). In the present embodiment, by arranging the lengthwise direction of the front plate 102, the lengthwise direction of the display panel 10 and the spacer lengthwise direction 110 to be parallel, deformation and concentration of stress in the spacer lengthwise direction 110 can be reduced. The front plate 102 is preferably in the form of a flat plate that is larger than the image display region (region or surface area in which the phosphors R, G and B are arranged) of the display panel (vacuum vessel 10). The front plate 102 is composed with a member that is transparent to visible light, and although a glass plate or polycarbonate plate, for example, can be used, a glass plate is particularly preferable from the viewpoint of optical characteristics. In order to give the vacuum vessel 10 a prescribed strength, the thickness of the front plate 102 is preferably 1.5 to 3.5 mm if it is composed of glass. In particular, the thickness of the front plate 102 is preferably set to be greater than the thicknesses of the face plate 11 and the rear plate 12 from the viewpoint of strength.
The material, shape, surface area and the like of the bonding member 121 is suitably set in consideration of the strength, impact absorption and thermal conductivity of the bonding member 121 and the flatness and the like of the front plate 102. Although there are no particular limitations on the bonding member 121, an adhesive that does not require high-temperature heating is preferably used to adhere the front plate 102 to the vacuum vessel 10 after forming the vacuum vessel 10. For example, a UV-curable resin adhesive can be used that is capable of adhering the front plate 102 composed of glass to the vacuum vessel 10 composed of glass at normal temperatures by irradiating with ultraviolet light. More specifically, an acrylic-based UV-curable resin adhesive can be used. Rigidity of the vacuum vessel 10, and particularly torsional rigidity in the planar direction, are increased by adhering the front plate 102 to the vacuum vessel 10 with the adhesive member 121. As a result, the thickness and weight of a conventionally required reinforcing member such as a reinforcing frame provided on the back of the rear plate 12 can be reduced considerably.
The plurality of fixing members 103 for fixing the vacuum vessel 10 to the rigid body in the form of the supporting member 108 are composed of two, mutually separated linear fixing members (103A and 103B) in the example shown in
The plurality of the fixing members 103 are arranged so that one of the fixing members 103A satisfies a linear symmetrical relationship with respect to the other fixing member 103B by having the center line 144 in the horizontal direction (first direction X of
The bonding members 122 are preferably provided on the surface of the vacuum vessel 10 in the same shape as the fixing members. Furthermore, although the width of the bonding members 122 can be set arbitrarily, in order to ensure an adequate bonding surface area between the fixing members and the vacuum vessel 10, the bonding members 122 preferably have the same shape as images of the fixing members 103 orthogonally projected onto the surface of the vacuum vessel 10 (surface of the rear plate 12) as shown in
Each fixing member (103A and 103B) is provided with a plate-shaped member 206 and a protruding portion 207 provided on the plate-shaped member 206, and the protruding portion 207 is given the function of a supporting point. The protruding portions 207 are provided on the side on the opposite side from the side of the plate-like members 206 that adheres to the rear plate 12. As a result of employing this configuration, the rigid body in the form of the supporting member 108 is fixed to the plurality of the fixing members 103, and the display panel (vacuum vessel 10) is fixed to the supporting member 108. The plate-like members 206 and the protruding portions 207 are firmly connected, and the connecting method may be a method such as caulking, press-fitting, welding or adhesion. The width and/or surface area of the plate-like members 206 is set to be larger than the width and/or surface area of the base portions of the protruding portions 207 (portions fixed to the plate-like members 206) at least at those portions where the protruding portions 207 are provided (directly beneath the protruding portions 207). This is to reduce stress generated in the vacuum vessel when an impact is applied to the vacuum vessel 10 through the protruding portions 207.
The plate-like members 206 and the protruding portions 207 are preferably formed from a metal such as aluminum, iron or magnesium. The advantages of forming the plate-like members 206 and the protruding portions 207 from metal are as follows:
In addition, favorable flatness can be obtained inexpensively by forming the plate-like members 206 by press-forming. The protruding portions 207 are able to function as interval-defining members, and the shape of the protruding portions 207 may be of any shape such as a cylindrical column, tetragonal column or polygonal column. A method such as header processing or machining can be used to fabricate the protruding portions 207. In addition, a structure can be provided in which thread cutting is carried out to give the protruding portions 207 the function of supporting points, and the fixing members (103A and 103B) firmly adhered to the vacuum vessel 10 are fixed to the supporting member 108 with screws. Although each fixing member (103A and 103B) is provided with six protruding portions 207, it is not necessary to use all of the protruding portions 207 for fixing to the supporting member 108. The numbers and locations of the protruding portions 207 used for fixing to the supporting member 108 can be suitably selected according to the shape and structure of the supporting member 108. For example, in the case of a supporting member 108 having a width in the horizontal direction that is equal to roughly half the width of the display panel, the two central protruding portions 207 among the six protruding portions 207 may be fixed to the supporting member 108. The greater the width in the horizontal direction of the supporting member 108 (support column 119), the greater the number of the protruding portions 207 or protruding portions 207 to the outside in the horizontal direction can be used for fixing. In addition, in the case of a supporting member 108 having a plurality of support columns 119, the protruding portions 207 can also be fixed to each of the support columns 119. In addition, caulking or press-fitting can be carried out at several locations at once by carrying out press-forming of the plate-like members 206 and the protruding portions 207 in combination. As a result, production cost of the fixing members can be reduced since the number of steps required for production can be decreased.
The supporting member 108 is provided with a support stand (pedestal) 118 for placing the display panel on an installation surface such as a desk or audio rack on which the image display apparatus is installed, and the support column 119 provided upright on the support stand 118 for holding the display screen of the display panel vertical with respect to the installation surface. Namely, the base portion of the support column 119 is fixed by the support stand 118. The supporting member 108 can be further provided with an angle adjustment portion so as to be able to adjust the angle of the display screen in all four directions relative to the support column 119. In addition, a rotating mechanism can be provided in the base portion of the support column 119 or in the pedestal 118 that allows rotation of the support column 119. In addition, although an example of composing the support stand 118 and the support column 119 with separate members is shown here, the support stand and the support column can also be in the form of a single member. In addition, a plurality of support columns 119 can also be provided.
Next, an explanation is provided of the configuration of the face plate 11 that contacts the spacers 14. A resistance adjustment layer 30 may be formed on the light shielding layer 17 shown in
A thin film separation layer 32 is formed on the resistance adjustment layer 30. The thin film separation layer 32 has vertical line portions 33V formed on each of the first resistance adjustment layers 31V of the resistance adjustment layer 30, and horizontal line portions 33H formed on each of the second resistance adjustment layers 31H of the resistance adjustment layer 30. The thin film separation layer 32 is formed by containing a binder and particles dispersed at a suitable density so that the surface has surface irregularities, thereby separating a thin film (metal back) 20 subsequently formed by vapor deposition and the like. A phosphor or silica and the like can be used for the particles that compose the thin film separation layer 32. The thin film separation layer 32 is formed to be slightly thinner than the light shielding layer 17, and in terms of a numerical example, the width of the horizontal line portions 33H of the thin film separation layer 32 is 260 μm, while the width of the vertical line portions 33V is 20 μm.
After forming the thin film separation layer 32, smoothing is carried out using lacquer and the like to form a smooth metal back layer 20. The film for smoothing is burned away by baking after having formed the metal back layer 20.
Following smoothing, the metal back layer 20 is formed by vapor deposition or other thin film formation process. As a result, separated metal back layers 20a, which are two-dimensionally separated in the first direction X and the second direction Y, are formed by the thin film separation layer 32. The separated metal back layers 20a are located superposing each of the light emitters R, G and B. In this case, gaps between the separated metal back layers 20a are of nearly the same width as the widths of the horizontal line portions 33H and the vertical line portions 33V of the thin film separation layer 32, and are 20 μm in the first direction X and 260 μm in the second direction Y. Furthermore, the metal back layer 20 is omitted from
A getter film 22 may also be formed superposing the metal back layer 20. In an FED, there are cases in which it is necessary to form the getter film 22 on a metal back layer in this manner to ensure the degree of vacuum over a long period of time. Since the action of the thin film separation layer is not lost after the metal back layer 20 is formed, the getter film 22 can be formed into separated getter films 22a that are two-dimensionally separated in a pattern similar to that of the metal back layer 20.
As shown in
Although the spacer contact layers 40 are preferably electrically conductive from the viewpoints of contact with the spacers, preventing of charge accumulation and the like, the use of insulated spacer contact layers is also permitted. Furthermore, the thin film separation layer and resistance adjustment layer explained in the above-mentioned examples may be omitted depending on the form and fabrication method of the metal back 20. Alternatively, the spacer contact layers 40 may also not be provided in addition to the thin film separation layer and the resistance adjustment layer. In such cases, the spacers 14 contact the metal back 20 and the metal back serves as a spacer contact layer.
As was explained using
However, in the image display apparatus as described above, even if an impact is applied to the vacuum vessel 10 from the supporting member 108, deformation of the spacers and shear stress generated in the contact portions of the spacers (spacer contact layers 40) can be reduced as previously explained using drawings such as
In the example shown in
The following indicates variations of the linear fixing members 103 described above. In a first variation as shown in
In a second variation as shown in
In a third variation as shown in
Deformation of the spacers 14 within the vacuum vessel 10 and shear stress generated in those portions contacting the spacers 14 (spacer contact layers 40) can be reduced in the above-mentioned variations as well. The linear fixing members described above are substantially not provided with the conventional function as members for reinforcing the vacuum vessel in the manner of a reinforcement frame provided on the back of the vacuum vessel. The front plate 102 fulfills that role with respect to rigidity of the vacuum vessel 10, and particularly with respect to torsional rigidity in the planar direction. Consequently, a member in the manner of a complex and heavy reinforcement frame conventionally provided on the back of the vacuum vessel 10 is no longer required by the display panel or image display apparatus.
The following provides an explanation of specific examples. First, an explanation is provided of those matters common to the image display apparatuses as claimed in the following Examples 1 to 3. Fixing members (103 or 503) are adhered and fixed to the surface of the rear plate 12 (side open to the atmosphere) that composes the vacuum vessel 10 by means of the bonding members 122. Details of the vacuum vessel 10 are basically the same as those explained using
The vacuum vessel 10 was formed by connecting the face plate 11 and the rear plate 12 in a vacuum by means of the connecting member 28, and the inside of the vacuum vessel 10 was held at a pressure of 1.0×10−5 Pa. The side wall 13 composed of glass and the bonding members 23 composed of indium were used for the connecting member 28. The face plate 11 and the rear plate 12 were connected by pressing the rear plate 12 against the face plate 11 while locally heating the bonding members in a vacuum chamber by irradiating with a laser. In addition, the plurality of long, narrow plate-like spacers 14 have the lengthwise direction 110 that is in the same direction as the lengthwise direction of the flat, rectangular vacuum vessel 10 (first direction X or horizontal direction). The plurality of long, narrow plate-like spacers 14 are arranged at intervals of 15 mm in a direction perpendicular to the lengthwise direction of the vacuum vessel 10 (second direction Y or vertical direction). The spacers 14 were composed of glass, and the thickness thereof was made to be 200 μm. The spacers 14 were provided on scanning wiring, and both end portions thereof in the lengthwise direction were fixed to the rear plate 12 by an inorganic adhesive (Aron Ceramic D, Toagosei Co., Ltd.). A silicone-based elastic resin adhesive in the form of TSE3944 (Momentive Performance Materials Japan LLC) was used for the bonding members 122. The silicone-based resin adhesive was coated at a thickness of 2 mm and width of 5 mm. In terms of practical use, for example, the coating thickness can be within the range of 1 to 5 mm and the width can be within the range of 0.5 to 5 mm. A silicone-based resin adhesive having a Young's modulus of 1 to 5 MPa and breaking elongation of 100% or more was used for the silicone-based resin adhesive.
In the present example, an image display apparatus was produced as shown in
The surface area over which the bonding members 122 are arranged can be made to be, for example, one-half the surface area of the rear plate 12. Subsequently, the fixing member 103 is adhered to the vacuum vessel 10 by curing the bonding members 122. The supporting member 108 was then fixed to the fixing member 103 by fastening with screws.
A vertical drop test from a height of 20 cm and a vibration test were carried out on the image display apparatus produced in the present example. Furthermore, the tests were carried out at that time such that impacts and vibrations were directly applied to the supporting member 108 (so that impacts and vibrations were applied to the vacuum vessel 10 from the supporting member 108 through the fixing member 103 and the bonding members 122). As a result, the vacuum vessel 10 was confirmed to be free of cracks, and stress lower than cracking stress of the vacuum vessel 10 was confirmed to have been generated. In addition, damage to the edge portions of the vacuum vessel 10 was also not observed. In addition, discharge phenomena was not confirmed when images were displayed with the image display apparatus after carrying out the vertical drop test as described above, and stable image display was able to be obtained over a long period of time. In addition, when the vacuum vessel 10 was disassembled, there was no damage to the spacers 14 and signs of crushing of the metal back 20 or spacer contact layers 40 by the spacers 14 were not observed.
The fixing member 103 used in the present example was provided with the configuration shown in
The shape of the plate-like members 206 was such that the wide portions measured 60 mm high×60 mm across, while the narrow portions measured 10 mm high×140 mm across. In addition, the thickness of the plate-like members 206 was 2 mm. Here, although the thickness was set to 2 mm, if metal or an alloy is used for the material, the thickness in terms of practical use is preferably 1 mm or more to less than 30 mm and more preferably less than 10 mm. In addition, zinc-plated sheet steel was used for the material of the plate-like members 206. In addition, a single protruding portion 207 was fixed in the center of a single wide portion 206. Furthermore, the height of the top of the protruding portions 207 (portion at the greatest distance from the back side of the rear plate 12) from the back side of the rear plate 12 was 25 mm. In terms of practical use, the height of the protruding portions 207 from the back side of the rear plate 12 is 5 mm or more to less than 30 mm in consideration of the arrangement of circuit boards and the like. Stainless steel was used for the material of the protruding portions 207. In addition, the pitch in the horizontal direction of the protruding portions 207 (supporting points) was 200 mm. Two fixing members (103A and 103B) were provided at an interval on the back side of the vacuum vessel 10 (side of the rear plate 12 exposed to the atmosphere). Furthermore, although two fixing members (103A and 103B) were used in the present example, the number of fixing members can be two or more. In addition, although the pitch in the vertical direction of the protruding portions 207 (supporting points) was 420 mm in the present example, in terms of practical use, it is within the range of 400 to 430 mm. The locations of the fixing members 103 relative to the vacuum vessel 10 is such that one of the fixing members 103A satisfies a linear symmetrical relationship with respect to the other fixing member 103B having the center line 144 in the horizontal direction (lengthwise direction 110 of the plate-like spacers 14) of the image display region (or rear plate 12) of the vacuum vessel 10 as the axis of symmetry. In addition, each of the fixing members (103A and 103B) was arranged so as to have a linearly symmetrical relationship having the center line 143 in the vertical direction of the image display region (or rear plate 12) as the axis of symmetry (state such that the image display region can be folded back in the vertical direction at the center line 143). The protruding portions 207 were in the form of cylindrical columns having a diameter of 16 mm. Furthermore, the shape of the protruding portions 207 may also be a tetragonal column or polygonal column instead of a circular column. These dimensions can be varied according to the rigidity of the vacuum vessel 10, rigidity of the front plate 102, mechanical properties of the bonding member 121, mechanical properties of the bonding members 122, and rigidity of the plurality of fixing members 103, and proper values can be derived for these values. In the present example, the bonding members 122 were in the form of two linear members. The shape of the bonding members 122 was made to be the same as the shape of the fixing members 103A and 103B (same shape as images of the fixing members orthogonally projected onto the surface of the vacuum vessel) (see
In addition, the rigidity of the fixing members 103 in the present example is less than that of the fixing members of Example 1. Consequently, the front plate 102 is adhered and fixed to the surface of the face plate 11 (side exposed to the atmosphere) that composes the vacuum vessel 10 using the bonding member 121 to increase the rigidity of the vacuum vessel 10. The front plate 102 is the same glass plate as that of the face plate 11 and the rear plate 12, and is larger than the image display region of the vacuum vessel 10. In the present example, the thickness of the front plate 102 was made to be 2.5 mm. Although the size was the same as that of the face plate 11, in the case of glass, the thickness is within the range of 1.5 to 3.5 mm. An acrylic-based UV-curable resin adhesive was used for the bonding member 121. More specifically, TB3042C (ThreeBond Co., Ltd.) was used for the bonding member 121. The acrylic-based UV-curable resin adhesive was coated over the entire surface of the side of the front plate 102 that opposes the face plate 11, and although it was coated to a thickness of 0.5 mm, in terms of practical use, the coating thickness is within the range of 0.1 to 1 mm. An advantage of combining the front plate 102 and the bonding member 121 in this manner is that reflection of external light and reflection of displayed images can be prevented in the image display apparatus.
A vertical drop test and vibration test were carried out on the image display apparatus produced in the present example in the same manner as in Example 1. As a result, the vacuum vessel 10 was confirmed to be free of cracks, and stress lower than cracking stress of the vacuum vessel 10 was confirmed to have been generated. In addition, stress generated in the vacuum vessel was able to be decreased by increasing the number of protruding portions 207 serving as supporting points. In addition, discharge phenomena was not confirmed when images were displayed with the image display apparatus after carrying out the vertical drop test as described above, and stable image display was able to be obtained over a long period of time. In addition, damage to the edge portions of the vacuum vessel 10 was also not observed. In addition, when the vacuum vessel 10 was disassembled, there was no damage to the spacers 14 and signs of crushing of the metal back 20 or spacer contact layers 40 by the spacers 14 were not observed.
In addition, the surface for mounting printed circuit boards was able to be made flat by employing the above-mentioned form for the plurality of the fixing members 103, and electrical circuits were able to be arranged at preferable locations without having to give hardly any consideration to the location of a reinforcement frame as in the prior art between the supporting member 108 and the rear plate 12. Consequently, design restrictions on electrical circuits were able to be reduced. An example of a design restriction is avoiding interference with the protruding portions 207. However, design restrictions were able to be diminished by drilling holes in a portion of a printed circuit board or plate to which a printed circuit board is fixed corresponding to the shape of the protruding portions 207, or by arranging printed circuit boards at locations where the protruding portions 207 were not present. In addition, effects resulting in considerable reductions in weight and costs of the display panel were able to be obtained in comparison with a reinforcement frame or other type of supporting member that was required in the prior art to obtain the same degree of strength for the display panel.
Furthermore, in a comparative example, two of the fixing members and bonding members 122 of the present Example 2 were rotated 90° (arranging so as be aligned in the vertical direction), and provided on the back of the rear plate 12 that composes the vacuum vessel 10. When a vertical drop test was carried out in the same manner as Example 1, a portion of the spacer contact layers 40 were confirmed to have been crushed by the spacers 14. In addition, damage to a portion of the spacers was also confirmed. Furthermore, the vertical direction refers to the direction perpendicular to the lengthwise direction 110 of the plate-like spacers 14.
Two fixing members (503A and 503B) used in the present example are provided with the configuration shown in
The present example is equivalent to a configuration in which the narrow portions 208 have been omitted (configuration in which wide portions and narrow portions are not connected) in comparison with Example 2. Thus, the plate-like members 506 in the present example are equivalent to the wide portions 206 in Example 2, and the plate-like members 506 measure 60 mm high×60 mm across. The protruding portions 507 in the present example are equivalent to the protruding portions 207 in Example 2. The units 510 are composed by fixing a single protruding portion 507 in the center of each plate-like member 506. In the present example, a single fixing member 503 was composed by arranging seven units 510 in a row in the horizontal direction (lengthwise direction 110 of the spacers 14) such that the pitch in the horizontal direction of the protruding portions 507 was 150 mm. Two fixing members 503 are adhered by the bonding members 122 on the back side (side of the rear plate 12 exposed to the atmosphere) of the vacuum vessel 10 so as to be separated in the vertical direction (direction perpendicular to the lengthwise direction 110 of the spacers 14). Furthermore, each unit was adhered so that the pitch in the vertical direction of the protruding portions 507 (supporting points) that compose each unit was 420 mm. Furthermore, although the number of the units 510 that compose a single fixing member (503A or 503B) is not limited to seven, the numbers of the units 510 that compose each row are preferably equal.
The plate-like members 506 (wide portions 206 in Example 2) and the protruding portions 507 (protruding portions 207 in Example 2) that compose the fixing members (503A and 503B) are formed in the same manner as Example 2. In addition, the shape, pitch of the supporting points, and method for fixing the plate-like members 506 and protruding portions 507 were also the same as in Example 2. In the present example, the shape of the bonding members 122 was made to be the same as the shape of the fixing members 503A and 503B (same shape as images of the fixing members orthogonally projected onto the surface of the vacuum vessel). The bonding members 122 were provided only in the region on the back side of region of the rear plate 12 surrounded by the connecting member 28.
When a vertical drop test was carried out in the same manner as Example 1, there was no damage to the spacers and signs of crushing of the metal back or spacer contact layers were not observed.
As a result of configuring the fixing members in the manner of the present example, the narrow portions 208 of Example 2 can be omitted, thereby further obtaining the effects of reducing the weight and cost of the display panel.
As has been described above, according to the present invention, deformation of the spacers and shear stress of spacer contact portions can be reduced and destruction of the vacuum vessel can be prevented even in cases in which strong impacts such as dropping impacts are applied to the image display apparatus. In addition, reduced thickness, light weight and lower costs of the image display apparatus can be realized.
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. 2009-118971, filed on May 15, 2009, which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | Kind |
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2009-118971 | May 2009 | JP | national |