JP6289584B2 - Display device - Google Patents

Description

  The present invention relates to a display device, and particularly, a protective cover that protects a display panel of the display device.

  Some display devices such as a liquid crystal display device using liquid crystal are arranged outdoors. In such a display device, a display surface for displaying an image on the display panel is often covered with a protective cover in order to protect it from external impacts and flooding due to rain. As the protective cover, for example, a glass protective cover disclosed in Patent Document 1 or a resin protective cover disclosed in Patent Document 2 is used.

  When such a protective cover is arranged on a display panel such as a flat panel, if there is an air layer between the display panel and the protective cover, the external light directed toward the display surface of the display panel is transparent. Are reflected on the front and back surfaces and the display surface. As a result, the problem that the visibility of the image displayed on a display surface falls arises.

  In order to solve the problem that the visibility is lowered, in the image display device disclosed in Patent Document 1, a gap between the display panel and the protective cover is filled with a transparent resin, or a light-transmitting adhesive sheet (hereinafter “ A transparent adhesive sheet ”may also be called.

JP 2009-216764 A JP 2007-114737 A

  When a glass protective cover is used as a protective cover as disclosed in Patent Document 1, the glass protective cover may be broken by an external impact. In this case, it becomes a fatal defect on display, and there is a possibility that the glass piece is scattered. In the technique disclosed in Patent Document 1, a glass scattering prevention sheet is attached to the surface of the glass protective cover in order to prevent glass scattering, but the glass scattering prevention sheet has the ability to absorb external impact. Since it does not have, it can hardly prevent the glass protective cover from cracking due to external impact.

  On the other hand, when a resin protective cover is used as a protective cover as disclosed in Patent Document 2, cracking due to external impact is unlikely to occur, but the resin protective cover warps due to heat, moisture absorption, etc. Is easily peeled off from the display panel. Furthermore, even when bubbles are generated on the adhesive surface of the resin protective cover due to outgas from the resin contained in the resin protective cover, the resin protective cover is easily peeled off from the display panel.

  In order to prevent the protective cover made of resin from peeling off, it is conceivable to increase the adhesive force of the transparent resin or the transparent adhesive sheet that fills the gap between the display panel and the protective cover. However, even if the resin protective cover can no longer be peeled off, the stress caused by the warping of the resin protective cover is transmitted to the display surface of the display panel, resulting in display defects such as display unevenness in the display panel, and the display quality is deteriorated. There is. In addition, as a countermeasure against peeling due to bubbles from the resin protective cover, it is effective to provide a barrier coat for suppressing outgassing on the adhesive surface of the resin protective cover, but there arises a problem that the cost of the display device increases.

  Therefore, the present invention has been made in view of the above-described problems, and an object of the present invention is to provide a technique that makes it difficult to break the protective cover and suppresses deterioration of display quality in the display panel.

The display device according to the present invention has a display panel having a display surface for displaying an image, a plate-shaped glass protective plate having translucency and covering and protecting the display surface, and translucency. And a first transparent adhesive material that is disposed in a gap between the display surface and the glass protective plate and bonds the display surface and the glass protective plate together. And the plate-shaped resin protective plate which has translucency, and covers and protects the said glass protective plate on the opposite side to the said 1st transparent adhesive material, and has translucency, and the said glass protective plate A second transparent adhesive material that is disposed in a gap between the protective plate made of glass and the protective plate made of glass and the protective plate made of resin, and an opening that faces the display surface of the display panel is provided, A first frame that is not bonded to either the glass protective plate or the resin protective plate. When the glass protective plate has a hook-like portion protruding from the outer shape of the first frame when the display surface is viewed from the front, the outer shape of the glass protective plate is obtained when the display surface is viewed from the front. Is larger than the outer shape of the resin protective plate .

  ADVANTAGE OF THE INVENTION According to this invention, while making a protective cover hard to break, the fall of the display quality in a display panel can be suppressed.

3 is a cross-sectional view of the display device according to Embodiment 1. FIG. 7 is a cross-sectional view of a display device according to Embodiment 2. FIG. 6 is a cross-sectional view of a display device according to Embodiment 3. FIG. 6 is a cross-sectional view of a display device according to Embodiment 4. FIG. 6 is a cross-sectional view of a display device according to Embodiment 4. FIG.

<Embodiment 1>
FIG. 1 is a cross-sectional view showing the configuration of the display device 11 according to the first embodiment. As shown in FIG. 1, the display device 11 includes a display panel 1, a front frame 3, a back frame 4, first and second transparent adhesive materials 5 and 7, a glass protective plate 6, And a resin protective plate 8. In the present embodiment, it is assumed that the display device 11 is a liquid crystal display device and the display panel 1 is a liquid crystal display panel.

  The display panel 1 is a panel that displays an image according to a signal from the outside, and has a translucent insulating substrate 1a, a counter substrate 1b, a back side polarizing plate 2a, and a display surface side polarizing plate 2b. Is provided.

  One main surface of the insulating substrate 1a is provided with a TFT array or the like in which a plurality of thin film transistors (abbreviated as “TFT”) (not shown) are arranged in an array. The counter substrate 1b is disposed to face the insulating substrate 1a (TFT array) through a liquid crystal layer (not shown).

  The back side polarizing plate 2a is provided on the surface of the insulating substrate 1a opposite to the surface facing the counter substrate 1b. The display surface side polarizing plate 2b is provided on the surface of the counter substrate 1b opposite to the surface facing the insulating substrate 1. In FIG. 1, known components such as a drive circuit and a circuit board for driving the liquid crystal are omitted in order to simply illustrate the display device 11.

  The display panel 1 configured as described above has a display surface for displaying an image. Specifically, a planar light source device (not shown) is provided on the back side polarizing plate 2a side of the display panel 1, and light from the device is emitted to the outside of the display panel 1 according to the polarization of the liquid crystal. The As a result of selectively emitting light from the display panel 1 in a plurality of pixels, an image is displayed on the display surface side polarizing plate 2 b side of the display panel 1. That is, in the present embodiment, the surface on the display surface side polarizing plate 2b side of the display panel 1 is the display surface. In the following description, the display surface of the liquid crystal panel 1 may be abbreviated as “display surface”. In addition, the surface opposite to the display surface of the display panel 1 (lower side toward the paper surface in FIG. 1) may be referred to as “the back surface of the display panel 1”.

  In the present embodiment, when the display surface is viewed from the front (when viewed from the top to the bottom in FIG. 1), the display panel 1 (the insulating substrate 1a, the counter substrate 1b, the back side polarizing plate). The shapes of 2a and the display surface side polarizing plate 2b) are rectangular. In FIG. 1, the left-right direction toward the paper surface is the longitudinal direction of the display panel 1.

  The front frame 3 and the back frame 4 contain the display panel 1 in a state of being fitted to each other. When the display surface is viewed from the front, the front frame 3 and the back frame 4 have a rectangular shape, similar to the display panel 1.

  The front frame 3 is a frame located on the display surface side of the display panel 1 when the display panel 1 is included integrally with the back frame 4. The front frame 3 is provided with an opening 3 a that faces the display surface of the display panel 1. With respect to each of the dimension in the longitudinal direction of the table frame 3 (hereinafter referred to as “longitudinal dimension”) and the dimension in the lateral direction (hereinafter referred to as “short dimension”), the opening 3a is on the display surface side. It is shorter than the polarizing plate 2b. A portion of the front frame 3 adjacent to the opening 3a covers and holds the peripheral edge of the display surface (display surface side polarizing plate 2b) of the display panel 1.

  The back frame 4 is a frame located on the back side of the display panel 1 when the display panel 1 is included integrally with the front frame 3. The back frame 4 includes a flat surface portion 4a that covers the back surface of the display panel 1 (display surface), in which the planar light source device is incorporated, and a protruding portion 4b that is provided upright from the flat surface portion 4a. Yes. The protrusion 4b is provided on the peripheral edge of the flat surface 4a and holds the side surface of the display panel 1 (insulating substrate 1a).

  In the present embodiment, the first transparent adhesive material 5, the glass protective plate 6, the second transparent adhesive material 7, and the resin protective plate 8 are formed on the display surface of the display panel 1 in this order. Yes.

  The glass protective plate 6 is a plate-like cover made of translucent glass and covers and protects the display surface of the display panel 1. Specifically, the glass protective plate 6 is provided outside the front frame 3, a portion of the display surface of the display panel 1 that can be viewed through the opening 3 a, and the opening 3 a of the front frame 3. Covers and protects the adjacent part. In the present embodiment, the periphery of the glass protective plate 6 is waterproofed.

  The first transparent adhesive material 5 is a translucent adhesive material, and is disposed in the gap between the display surface and the glass protective plate 6 in the opening 3a of the front frame 3, and the display surface and the glass The protective plate 6 is bonded together.

  The resin protective plate 8 is a plate-like cover made of a resin having translucency, and covers and protects the glass protective plate 6 on the side opposite to the first transparent adhesive material 5. Even if it is a sheet-like thing like a polarizing plate as the resin protective plate 8, there is an effect of preventing the broken pieces when the glass is broken, but not only such a broken piece preventing effect. In order to produce the effect of preventing the glass from being broken, the thickness of the resin protective plate 8 is desirably 1 mm or more. In the present embodiment, the periphery of the resin protective plate 8 is waterproofed. Moreover, when the display surface is viewed from the front, the front frame 3, the glass protective plate 6, and the resin protective plate 8 have substantially the same size.

  The second transparent adhesive material 7 is a translucent adhesive material, and is disposed in the gap between the glass protective plate 6 and the resin protective plate 8, and the glass protective plate 6 and the resin protective plate. 8 is pasted together.

  According to the display device 11 according to the present embodiment as described above, since the resin protective plate 8 is located on the display surface of the display panel 1 via the glass protective plate 6 and the like, the resin protective plate is used. The stress transmitted to the display surface due to the warpage of 8 is reduced by the glass protective plate 6 or the like. Therefore, display defects such as display unevenness in the display panel 1 can be suppressed, and deterioration in display quality can be suppressed. Further, according to the display device 11 according to the present embodiment, the second transparent adhesive material 7 and the plate-shaped resin protective plate 8 are located on the front side (outside) of the glass protective plate 6. The external impact transmitted to the glass protective plate 6 is absorbed by the second transparent adhesive material 7 and the resin protective plate 8. Therefore, the crack of the glass protective plate 6 due to external impact can be reduced.

  In the above display device 11, it is desirable that the adhesive strength of the second transparent adhesive material 7 is higher than the adhesive strength of the first transparent adhesive material 5. In such a case, since the adhesive strength of the second transparent adhesive material 7 is relatively high, the resin protective plate 8 can be prevented from being peeled off from the glass protective plate 6 due to warping or outgassing. Further, since the adhesive strength of the first transparent adhesive material 5 is relatively weak, it can be disassembled relatively easily when a defect is discovered and repaired after the display device 11 is completed. Since the glass protective plate 6 does not warp or outgas like the resin protective plate 8, the adhesive strength of the first transparent adhesive material 5 can be made relatively weak.

  In the display device 11 described above, it is desirable that the hardness of the first transparent adhesive material 5 is lower than the hardness of the second transparent adhesive material 7. In such a case, the stress generated by the warp of the resin protective plate 8 is easily absorbed by the first transparent adhesive material 5. Therefore, it is possible to reliably suppress the display quality deterioration in the display panel 1.

  In the first embodiment, the front frame 3 is provided as a means for holding the display panel 1. However, the display panel 1 is not necessarily held by the front frame 3, and other holding means (illustrated) May not be used.

<Embodiment 2>
FIG. 2 is a cross-sectional view showing the configuration of the display device 11 according to the second embodiment. Hereinafter, in the display device 11 according to the present embodiment, the same components as those of the display device 11 according to the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  In the first embodiment, when the display surface is viewed from the front, the front frame 3, the glass protective plate 6, and the resin protective plate 8 have substantially the same size. In such a case, in order for the display device 11 to be fixed in a casing or the like (not shown) in which the display device 11 is incorporated, a fixing portion fixed to the casing or the like is provided on the front frame 3 or the back frame 4. It is necessary to provide it. However, restricting the target for providing the fixed portion to the front frame 3 or the back frame 4 restricts the design of the housing and the like, and narrows the application range of the display device 11.

  Therefore, in the display device 11 according to the present embodiment, when the display surface of the display panel 1 is viewed from the front, the glass protective plate 6 has a hook-like portion 6a protruding from the outer shape of the resin protective plate 8. doing. That is, when the display surface is viewed from the front, the size of the protective plate 6 made of glass is larger than the size of the protective plate 8 made of resin.

  According to the display device 11 according to the present embodiment as described above, the display device 11 can be fixed to the housing or the like by sandwiching the hook-like portion 6a protruding from the outer shape of the resin protective plate 8. . Therefore, the application range of the display device 11 can be expanded.

<Embodiment 3>
FIG. 3 is a cross-sectional view showing the configuration of the display device 11 according to the third embodiment. Hereinafter, in the display device 11 according to the present embodiment, the same components as those of the display device 11 according to the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  In the configuration in which the glass protective plate 6 is provided outside the front frame 3 as in the display device 11 according to the first embodiment, a large external stress is easily applied to the first transparent adhesive material 5. There is a possibility that the glass protective plate 6 is peeled off from the interface of the first transparent adhesive material 5. In particular, when an adhesive material having relatively low adhesive strength is used as the first transparent adhesive material 5 in order to facilitate disassembly such as repair, the possibility becomes higher.

  Therefore, in the display device 11 according to the present embodiment, when the display surface of the display panel 1 is viewed from the front, the size increases in the order of the opening 3a, the glass protective plate 6, and the front frame 3. And the part adjacent to the opening 3a in the front frame 3 (1st frame) covers and hold | maintains the peripheral part of the surface by which the 2nd transparent adhesive material 7 of the glass-made protective plates 6 was arrange | positioned.

  The second transparent adhesive material 7 is disposed in the gap between the glass protective plate 6 and the resin protective plate 8 in the opening 3 a of the front frame 3. The glass protective plate 6 and the resin protective plate 8 are provided on the inner side and the outer side of the front frame 3, respectively.

  According to the display device 11 according to the present embodiment as described above, the outer stress applied to the first transparent adhesive material 5 since the front frame 3 covers and holds the peripheral edge of the glass protective plate 6. Can be reduced. Therefore, the possibility that the display panel 1 or the glass protective plate 6 is peeled off from the first transparent adhesive material 5 can be reduced.

  In the present embodiment, when the display surface of the display panel 1 is viewed from the front, the size of the glass protective plate 6 and the size of the insulating substrate 1a of the display panel 1 are substantially the same. And the upper end of the projection part 4b which the back frame 4 has is located above the lower end of the glass-made protection board 6, and the side surface of the said projection part 4b upper part contact | abuts the side surface of the glass-made protection board 6 Yes. As a result, the protrusion 4b of the back frame 4 (second frame) holds the side surface of the display panel 1 (insulating substrate 1a) and the side surface of the glass protective plate 6.

  According to such a display device 11 according to the present embodiment, the protrusion 4b holds the side surface of the display panel 1 and the side surface of the glass protective plate 6, so that the glass protective plate 6 and the display panel 1 are It is possible to suppress the gap between them.

<Embodiment 4>
4 and 5 are cross-sectional views showing the configuration of the display device 11 according to the fourth embodiment. Hereinafter, in the display device 11 according to the present embodiment, the same components as those of the display device 11 according to the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  In the above embodiment, the thickness of the resin protective plate 8 is made uniform in order to suppress warping of the resin protective plate 8 due to heat, moisture absorption, or the like. However, when the surface of the resin protective plate 8 opposite to the second transparent adhesive material 7 is used as a design surface, if the thickness of the resin protective plate 8 is uniform, design design is restricted. Become. Therefore, in the display device 11 according to the present embodiment, the resin protective plate 8 has a non-uniform thickness.

  As an example, as shown in FIG. 4, by changing the thickness of the resin protective plate 8 so as to gradually increase from one side to the opposite side, The other surface (the upper surface in FIG. 4) is inclined with respect to the surface (the lower surface in FIG. 4).

  As another example, as shown in FIG. 5, the thickness of the resin protective plate 8 is changed so as to gradually become thinner from the sides on both sides toward the central portion. The surface (the upper surface in FIG. 4) is a curved surface.

  According to the display device 11 according to the present embodiment as described above, the design freedom of the design of the resin protective plate 8 can be improved.

  DESCRIPTION OF SYMBOLS 1 Display panel, 3 front frame, 3a opening, 4 back frame, 4a plane part, 4b protrusion part, 5 1st transparent adhesive material, 6 glass protective plate, 6a bowl-shaped part, 7 2nd transparent adhesive material, 8 resin Protection plate made of 11 display device.

Claims (6)

A display panel having a display surface for displaying an image;
A plate-shaped glass protective plate having translucency and covering and protecting the display surface;
A first transparent adhesive material having translucency, disposed in a gap between the display surface and the glass protective plate, and bonding the display surface and the glass protective plate;
A plate-shaped resin protective plate having translucency and covering and protecting the glass protective plate on the side opposite to the first transparent adhesive material;
A second transparent adhesive material having translucency, disposed in a gap between the glass protective plate and the resin protective plate, and bonding the glass protective plate and the resin protective plate;
An opening that faces the display surface of the display panel is provided, and includes a first frame that is not bonded to either the glass protective plate or the resin protective plate,
When the glass protective plate has a hook-like portion protruding from the outer shape of the first frame when the display surface is viewed from the front, the outer shape of the glass protective plate is obtained when the display surface is viewed from the front. Is larger than the outer shape of the resin protective plate .   A second frame having a flat portion covering the surface of the display panel opposite to the glass protective plate, and a protrusion that is provided upright from the flat portion and holds the side surface of the display panel; The display device according to claim 1.   The display device according to claim 2, wherein the display panel is included in a state in which the first frame and the second frame are fitted to each other. 4. The display device according to claim 1, wherein the hook-shaped portion is sandwiched by a housing that does not include the first frame and is fixed to the housing. 5.   The display device according to any one of claims 1 to 4, wherein the resin protective plate is a polarizing plate.   6. The display device according to claim 1, wherein the protective plate made of resin is a sheet having a plate thickness of 1 mm or more.

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