JP6374786B2 - Liquid crystal display - Google Patents

Description

  The present invention relates to a liquid crystal display (LCD) having a backlight device, a liquid crystal display panel, and a transparent protective plate such as a cover glass.

  FIG. 5 shows a cross-sectional view of the basic configuration of an example of a conventional LCD. As shown in FIG. 5, the light guide plate 22 is placed on the bottom surface of the concave container 21 made of aluminum (Al), zinc (Zn) plated steel, or the like whose upper end is an open end opened to the outside, It is joined to the bottom surface of the container 21 by a double-sided adhesive tape or the like. The backlight device 32 includes a light guide plate 22, a lens (bead) diffusion sheet placed on the light guide plate 22 and having a large number of lens-like protrusions or bead-like protrusions, and a reflective polarizing film (Dual Brightness Enhancement Film). And an optical sheet 23 as a light reuse sheet. A liquid crystal display panel 25 is installed on the backlight device 32 at intervals. The inner surface of the side wall portion 31a of the frame body 31 is attached to the outer surface of the side wall 21a of the container 21 by means such as adhesion and screwing, and extends to the inside of the container 21 in plan view at the upper end of the frame body 31. A collar portion 31c is formed. A support member 34 made of a resin or the like for supporting the base portion of the collar portion 31 c of the frame body 31 at the end of the bottom surface of the container 21 is installed inside the container 21.

  The surface of the liquid crystal display panel 25 on the transparent protective plate 27 side (the surface on the display side) is centered on the surface of the transparent protective plate 27 on the liquid crystal display panel 25 side by a first adhesive layer 26 made of UV curable resin or double-sided tape. It is glued to. Further, the peripheral edge portion of the surface of the transparent protective plate 27 on the liquid crystal display panel 25 side is bonded to the collar portion 31 c of the frame body 31 by an adhesive sheet 35. Further, the peripheral portion of the surface of the liquid crystal display panel 25 on the backlight device 32 side is surrounded by the second adhesive layer 29 made of the same double-sided tape as the first adhesive layer 26 and the peripheral portion of the backlight device 32 and the support member 34. It is adhered to the extended portion 34a.

  Further, the frame 31 is attached to the container 21 by inserting and locking the hook-shaped locking portion 21b into the through hole 31b formed in the side wall portion 31a. Further, there is a gap G between the backlight device 32 and the liquid crystal display panel 25 (see, for example, Patent Document 1).

  Note that the backlight device 32 may include a retardation plate, a linear polarizing plate, and the like, and the liquid crystal display panel 25 may include a retardation plate, a linear polarizing plate, a touch panel, and the like.

JP 2014-115588 A

  In the conventional LCD shown in FIG. 5, the liquid crystal display panel 25 has a peripheral portion of the surface opposite to the display side by the second adhesive layer 29 and a peripheral portion of the backlight device 32 and an extended portion 34 a of the support member 34. Because of being bonded to the two types of members, stress is applied to the peripheral portion of the surface opposite to the display side, and there is a problem in that the display quality is likely to deteriorate at the peripheral portion such as a decrease in contrast and white spots. . Further, since the side surface of the backlight device 32 and the side surface of the extending portion 34a of the support member are in contact with each other, when the backlight device 32 generates heat and expands during driving, stress due to the expansion deformation is generated. The reason is that it is added to the peripheral edge of the transparent protective plate 27 via the support 34, the collar portion 31c, and the adhesive sheet 35, and further affects the peripheral edge of the display side surface of the liquid crystal display panel 25 to deteriorate the display quality. There was a problem of becoming.

  The present invention has been completed in view of the above-described problems, and an object of the present invention is to reduce and eliminate the stress applied to the peripheral portion of the liquid crystal display panel to suppress deterioration in display quality.

  The liquid crystal display device according to the present invention includes a concave container having one open end, a backlight device placed on the bottom surface of the container, an inner end of the container in plan view, and an open end of the container A frame having a flange that covers the side wall of the container, and an inner frame positioned at an end of the bottom surface of the container, and a surface on the backlight device side A transparent protective plate bonded to the liquid crystal display panel, and the liquid crystal display panel has a first gap between the backlight device and the frame body. Has a second gap between the collar and the transparent protective plate, and an opening formed by the collar in a plan view is outside the outer shape of the liquid crystal display panel. The body has a third gap between the body and the side of the backlight device. Rutotomoni has the extending portion entering the first gap is configured such that the peripheral portion of the said extending portion liquid crystal display panel is bonded by a bonding material.

  In the liquid crystal display device of the present invention, preferably, the collar portion has a protrusion on a surface facing the transparent protective plate.

  In the liquid crystal display device of the present invention, it is preferable that the inner frame has a fourth gap between the inner frame and the collar.

  In the liquid crystal display device of the present invention, it is preferable that the inner frame has a recess for reducing a contact area on at least one of a surface in contact with an end of the bottom surface of the container and a surface on the collar side. doing.

  In the liquid crystal display device of the present invention, it is preferable that the transparent protective plate has a light-shielding layer on the peripheral portion of the surface on the backlight device side from the peripheral portion of the liquid crystal display panel to the collar portion.

  In the liquid crystal display device of the present invention, preferably, the thickness of the bonding material for bonding the liquid crystal display panel and the transparent protective plate is 0.3 mm or less.

  The liquid crystal display device of the present invention includes a concave container whose one end is an open end, a backlight device placed on the bottom surface of the container, and extends inside the container in plan view and covers the open end of the container A frame having a flange and having a side wall locked to a locking portion of the side wall of the container, an inner frame positioned at the end of the bottom of the container, and a central portion of the surface on the backlight device side are liquid crystal A liquid crystal display device having a transparent protective plate bonded to the display panel, the liquid crystal display panel having a first gap between the backlight device and the frame body in plan view The opening formed by the collar portion is outside the outer shape of the liquid crystal display panel, and has a second gap between the collar portion and the transparent protective plate, and the inner frame is connected to the side surface of the backlight device. An extension part that has a third gap in between and enters the first gap. And has, since and the peripheral portion of the extending portion and the liquid crystal display panel are joined by bonding material, the following effects. That is, since there is a first gap between the liquid crystal display panel and the backlight device, the liquid crystal display panel is not directly affected by thermal expansion due to heat generation of the backlight device. In addition, since the opening formed by the flange portion in the plan view is outside the outer shape of the liquid crystal display panel, the frame body is less likely to generate stress due to the flange portion at the peripheral edge portion of the liquid crystal display panel. Since the frame has a second gap between the collar portion and the transparent protective plate, stress due to deformation of the inner frame and the collar portion is not transmitted to the transparent protective plate. It is possible to suppress deterioration of display quality due to the influence of stress on the peripheral portion of the display side surface. Since the inner frame has a third gap between the inner frame and the side surface of the backlight device, the inner frame is not directly affected by thermal expansion due to heat generated when the backlight device is driven. In addition, the inner frame has an extension part that enters the first gap, and the extension part and the peripheral part of the liquid crystal display panel are joined by a joining material, so that the liquid crystal is made by a single member. Since the peripheral portion of the display panel can be supported, stress is hardly generated at the peripheral portion of the liquid crystal display panel. Further, since the side wall of the frame is locked to the locking portion of the side wall of the container, the frame is not firmly fixed to the container, and thermal expansion or the like occurs in components such as the backlight device. When it is done, it can be slightly absorbed to relieve the stress generated in the container and the frame. As described above, it is possible to reduce the stress applied to the peripheral portion of the liquid crystal display panel and suppress the display quality from deteriorating.

  In the liquid crystal display device of the present invention, preferably, since the flange portion has a protrusion on the surface facing the transparent protective plate, an external force is applied to the peripheral portion of the transparent protective plate from the side opposite to the flange portion. In this case, the protrusion functions as a height restricting portion that restricts the displacement of the height of the peripheral edge of the transparent protective plate. As a result, the effect of reducing the stress applied to the peripheral portion of the liquid crystal display panel and suppressing deterioration of the display quality is enhanced.

  In the liquid crystal display device of the present invention, preferably, since the inner frame has a fourth gap between the inner frame and the flange, the stress due to the deformation of the inner frame is more difficult to be transmitted to the transparent protective plate. .

  In the liquid crystal display device of the present invention, it is preferable that the inner frame has a recess for reducing the contact area on at least one of the surface in contact with the end of the bottom surface of the container and the surface on the collar portion side. For this reason, the stress applied to the collar portion from the inner frame can be reduced. In particular, it is advantageous when the width of the collar portion is reduced for miniaturization.

  In the liquid crystal display device of the present invention, preferably, the transparent protective plate has a light shielding layer on the peripheral portion of the surface on the backlight device side from the peripheral portion to the flange portion of the liquid crystal display panel. Need not be used as a light shielding part.

  In the liquid crystal display device of the present invention, preferably, the thickness of the bonding material for bonding the liquid crystal display panel and the transparent protective plate is 0.3 mm or less, so the liquid crystal display panel and the transparent protective plate are bonded by a thin bonding material. It becomes possible to do. Further, a thin liquid crystal display device is obtained.

1A and 1B are diagrams showing an example of an embodiment of the liquid crystal display device of the present invention, respectively, and are cross-sectional views of the basic configuration of the liquid crystal display device. FIGS. 2A and 2B are views showing another example of the embodiment of the liquid crystal display device of the present invention, and are sectional views of the basic configuration of the liquid crystal display device. FIGS. 3A and 3B are diagrams showing another example of the embodiment of the liquid crystal display device of the present invention, and are cross-sectional views of the basic configuration of the liquid crystal display device. FIG. 4 is a view showing another example of the embodiment of the liquid crystal display device of the present invention, and is an enlarged cross-sectional view of the peripheral edge portion of the transparent protective plate of the liquid crystal display device and its periphery. FIG. 5 is a diagram showing an example of a conventional liquid crystal display device, and is a cross-sectional view of the basic configuration of the liquid crystal display device.

  Embodiments of an LCD according to the present invention will be described below with reference to the drawings. However, each drawing referred to below shows a main part for explaining the LCD of the present invention among the constituent members in the embodiment of the LCD of the present invention. Therefore, the LCD according to the present invention may include well-known components such as a circuit board, a wiring conductor, a control IC, and an LSI that are not shown in the drawing.

  1A and 1B are diagrams showing an example of an embodiment of the LCD of the present invention, respectively, and are cross-sectional views of the basic configuration of the LCD. As shown in FIG. 1, the LCD has a concave container 1 whose one end is an open end, a backlight device 12 placed and fixed on the bottom surface of the container 1, and an inner side of the container 1 in plan view. A frame 11 that has a collar portion 11c that extends and covers the open end of the container 1 and has the side wall portion 11a attached to the engaging portion 1b of the side wall 1a of the container 1, and an interior located at the end of the bottom surface of the container 1 An LCD having a frame 4 and a transparent protective plate 7 having a central portion of the surface on the backlight device 12 side bonded to the liquid crystal display panel 5. The liquid crystal display panel 5 is connected to the backlight device 12. The frame 11 has a first gap G1 between them, and the frame 11 has an opening formed by the flange portion 11c in a plan view outside the outer shape of the liquid crystal display panel 5, and the flange portion 11c and the transparent protective plate 7 A second gap G2 between the inner frame 4 and the inner frame 4. The third gap G3 is provided between the side face of the display device 12 and the extension part 4a that enters the first gap G1. The extension part 4a and the peripheral part of the liquid crystal display panel 5 Are joined by the joining material 9.

  With the above configuration, the following effects can be obtained. That is, since there is the first gap G1 between the liquid crystal display panel 5 and the backlight device 12, the liquid crystal display panel 5 is not directly affected by the thermal expansion caused by the heat generated by the backlight device 12. Further, since the frame 11 has an opening formed by the flange portion 11c in a plan view and is outside the outer shape of the liquid crystal display panel 5, a stress caused by the flange portion 11c is generated at the peripheral portion of the liquid crystal display panel 5. It will be difficult. Since the frame 11 has the second gap G <b> 2 between the collar portion 11 c and the transparent protection plate 7, stress due to deformation of the inner frame body 4 and the collar portion 11 c is not transmitted to the transparent protection plate 7. Therefore, it is possible to suppress the display quality from deteriorating due to the influence of stress on the peripheral portion of the display side surface of the liquid crystal display panel 5. Since the inner frame body 4 has the third gap G3 between the inner frame body 4 and the side surface of the backlight device 12, the inner frame body 4 is not directly affected by thermal expansion due to heat generated when the backlight device 12 is driven. . Further, the inner frame body 4 has an extending portion 4a that enters the first gap G1, and the extending portion 4a and the peripheral edge portion of the liquid crystal display panel 5 are joined by the joining material 9, Since the peripheral part of the liquid crystal display panel 5 can be supported by a single member, the peripheral part of the liquid crystal display panel 5 is less likely to generate stress. Further, since the side wall 11a of the frame 11 is locked to the locking portion 1b of the side wall 1a of the container 1, the frame 11 is not firmly fixed to the container 1, and the backlight device 12 or the like When thermal expansion or the like occurs in the component parts, it can be slightly absorbed to relieve the stress generated in the container 1 and the frame 11. As described above, it is possible to reduce the stress applied to the peripheral portion of the liquid crystal display panel 5 and suppress the display quality from deteriorating.

  In the LCD of the present invention, as shown in FIG. 4, the collar portion 11 c preferably has a protrusion 11 d on the surface facing the transparent protective plate 7. In this case, when an external force is applied to the peripheral edge portion of the transparent protective plate 7 from the side opposite to the flange portion 11c, the protrusion 11d functions as a height restricting portion that restricts the displacement of the peripheral edge portion of the transparent protective plate 7. To do. As a result, the effect of reducing the stress applied to the peripheral edge of the liquid crystal display panel 5 and suppressing the deterioration of the display quality is enhanced. The protrusion 11d has a lower height than the second gap G2, but the height of the second gap G2 is about 0.2 mm to 0.5 mm, and the height of the protrusion 11d is 0. It is good that it is about 1 mm to 0.15 mm. Therefore, the distance between the top of the protrusion 11d and the peripheral edge of the transparent protective plate 7 is preferably about 0.05 mm to 0.4 mm. If it is less than 0.05 mm, the protrusion 11d tends to come into contact with the peripheral edge of the transparent protective plate 7 when the LCD is slightly deformed due to thermal expansion or the like. If it exceeds 0.4 mm, it will be difficult to function as a height regulating part, and the effect of reducing the stress applied to the peripheral part of the liquid crystal display panel 5 tends to be difficult to be exhibited. Further, the protrusion 11d may be located near the outer end of the surface of the collar portion 11c facing the transparent protective plate 7, particularly outside the center of the collar portion 11c. In this case, when an external force is applied to the peripheral edge portion of the transparent protective plate 7 from the side opposite to the collar portion 11c, the protrusion 11d easily comes into contact with the peripheral edge portion of the transparent protective plate 7 and easily functions as a height regulating portion. Therefore, the effect of reducing the stress applied to the peripheral portion of the liquid crystal display panel 5 tends to be easily exhibited. In addition, the protrusion 11d may have a flat top surface or a protruding curved surface. In this case, when an external force is applied to the peripheral edge of the transparent protective plate 7 from the side opposite to the flange portion 11c, the protrusion 11d can easily relieve the stress. The protrusion 11d can have various shapes such as a circular shape, an elliptical shape, a triangular shape, a quadrangular shape, a pentagonal or higher polygonal shape, and a belt shape in plan view. Further, a plurality of protrusions 11d can be provided, or can be provided continuously or intermittently in a strip shape or a bank shape over the entire circumference of the collar portion 11c. Further, the protrusion 11d may be provided integrally with the collar portion 11c, but is made of a resin or metal formed as a separate member on the surface of the collar portion 11c facing the transparent protective plate 7. It may be made of ceramic or the like.

  The display side surface of the liquid crystal display panel 5 is formed on a transparent protective plate 7 made of a glass plate, an acrylic plate, or the like by a transparent bonding material 6 such as a highly transparent adhesive transfer tape (OCA). It is joined. Further, the peripheral edge portion of the surface opposite to the display side of the liquid crystal display panel 5 is connected to the extension portion 4a of the inner frame 4 by a bonding material 9 made of a double-sided adhesive tape or the like of white or the like that does not necessarily require transparency. It is joined. The bonding material 9 may be provided over the entire circumference, but a plurality of bonding materials 9 may be provided intermittently at intervals. Furthermore, when the planar view shape of the liquid crystal display panel 5 is a quadrangular shape, the bonding material 9 may be provided in the center part of the two opposite sides of the liquid crystal display panel 5 or the center part of each side. In this case, it can suppress more that a stress is added to the peripheral part of the liquid crystal display panel 5. FIG.

  The bonding material 9 includes a buffer member made of a low-resilience resin, such as a silicone resin, polyurethane, foaming polyurethane (urethane foam), or a microcell polymer sheet, a shock-absorbing resin, and the like. It is preferable to have an adhesive layer and an adhesive layer on the lower surface. In this case, it is possible to further suppress the stress from being applied to the peripheral portion of the liquid crystal display panel 5.

  Preferably, a light-shielding layer 8 made of a light-shielding resin or the like having a dark color such as black, black-brown, or amber is formed from the peripheral edge of the surface of the transparent protective plate 7 on the backlight device 12 side to the collar 11c. Good to be. In this case, it is not necessary to use the collar portion 11c as a light shielding portion, which is advantageous for stress relaxation.

  The thickness of the bonding material 6 for bonding the liquid crystal display panel 5 and the transparent protective plate 7 is preferably 0.3 mm or less. In this case, the liquid crystal display panel 5 and the transparent protective plate 7 can be bonded by the thin bonding material 6. In addition, the LCD is thinned. The thickness of the bonding material 6 is preferably 0.1 mm or more. If it is less than 0.1 mm, the liquid crystal display panel 5 tends to be easily affected by the deformation of the transparent protective plate 7.

  The frame 11 is attached to the container 1 by inserting and locking the locking portion 1b formed of the protrusion into the through hole 11b formed in the side wall portion 11a. In this case, the locking part 1b may be in the side wall part 11a, and the through hole 11b may be in the side wall 1a. Moreover, the side wall part 11a may exist in the inner surface side of the side wall 1a. And the container 1 and the frame 11 are assembled | attached by inserting the container 1 into the inner side of the side wall part 11a from the downward direction, and making the latching | locking part 1b latch to the through-hole 11b.

  The inner frame 4 is made of a resin material such as acrylic resin, polyimide, polyamide, polyimide amide, silicone resin, or polyurethane. The inner frame 4 may be a dense body. However, in order to relieve stress applied to the collar portion 11c and reduce the weight, the inner frame body 4 has a hollow structure having a cavity inside, and a notch structure having a notch portion and a recess on the surface. It is good to have. In particular, as shown in FIG. 1B, the inner frame 44 has a recess for reducing the contact area on at least one of the surface in contact with the end of the bottom surface of the container 1 and the surface on the side of the collar portion 11c. It is preferable. If the inner frame 44 has a surface in contact with the collar portion 11c, a recess is formed on the surface. And in the case of said structure, the stress added to the collar part 11c from the internal frame 44 can be reduced. In particular, it is advantageous when the width of the collar portion 11c is reduced for miniaturization. In addition, when the inner frame 44 is made of resin and is made of resin that is cooled and cured after heating, and the inner frame 44 is a dense structure without a recess, the surface is recessed. Occurs and the contact surface is likely to be rattled. In the case where the inner frame body 44 has a recess for reducing the contact area, the surface that contacts the end of the bottom surface of the container 1 and the surface on the collar portion 11c side are not depressed, and the contact surface The occurrence of rattling is eliminated. The inner frame 4 may be a single member formed in a frame shape or may be composed of a plurality of members.

  The inner frame 44 is a recess for reducing a contact area on at least one of a surface (referred to as a contact surface a) that contacts the end of the bottom surface of the container 1 and a surface (referred to as a contact surface b) that contacts the collar portion 11c. In a plan view, the area of the opening of the recess is preferably 50% or more of the area of the contact surface a (the area when there is no recess). In this case, there is a tendency that rattling is unlikely to occur on the contact surface a. Moreover, it is preferable that the area of the opening of a recessed part is 50% or more of the area of the contact surface b (area when there is no recessed part) by planar view. In this case, there is a tendency that rattling is unlikely to occur on the contact surface b, and the effect of reducing the stress applied from the inner frame 44 to the collar portion 11c is enhanced.

  The first gap G1 between the liquid crystal display panel 5 and the backlight device 12 is preferably about 0.25 mm to 1 mm. If it is less than 0.25 mm, the liquid crystal display panel 5 and the backlight device 12 tend to come into contact with each other due to deformation due to thermal expansion of the backlight device 12. If it exceeds 1 mm, the LCD tends to increase in size.

  The backlight device 12 may include a retardation plate, a linear polarizing plate, and the like, and the liquid crystal display panel 5 may include a retardation plate, a linear polarizing plate, a touch panel, and the like.

  In the LCD of the present invention, as shown in FIGS. 2A and 2B, the inner frame bodies 54 and 64 preferably have a lower width smaller than the upper width of the extending portions 54a and 64a. In this case, the extending portions 54a and 64a are easily bent toward the backlight device 12, and it is possible to suppress the stress from being strongly applied to the peripheral portion of the liquid crystal display panel 5. Further, since the third gap G3 between the side surface of the backlight device 12 and the inner frames 54 and 64 is widened, there is an effect that the inner frames 54 and 64 are not easily affected by the thermal expansion of the backlight device 12. Rise.

  In the LCD of the present invention, as shown in FIGS. 3A and 3B, it is preferable that the inner frames 74 and 84 have a fourth gap G4 between the collar portion 11c. In this case, the stress due to the deformation of the inner frames 74 and 84 is further less likely to be transmitted to the transparent protective plate 7. The second gap G2 is preferably smaller than the fourth gap G4. In this case, particles such as dust can be prevented from entering the inside of the LCD from the outside through the second gap G2. In FIGS. 3A and 3B, reference numerals 74a and 84a denote extending portions of the inner frame bodies 74 and 84, respectively.

  The LCD of the present invention is not limited to the above-described embodiment, and may include appropriate design changes and improvements.

  The LCD of the present invention can be applied to various electronic devices. The electronic devices include automobile route guidance system (car navigation system), ship route guidance system, aircraft route guidance system, smartphone terminal, mobile phone, tablet terminal, personal digital assistant (PDA), video camera, digital still camera, electronic Notebook, electronic book, electronic dictionary, personal computer, copier, game device terminal, television, product display tag, price display tag, industrial programmable display, car audio, digital audio player, facsimile, printer, cash There are automatic teller machines (ATMs), vending machines, head-up display devices, projector devices, digital display watches, and the like.

DESCRIPTION OF SYMBOLS 1 Container 1a Side wall 1b Locking part 2 Light guide plate 3 Optical sheet 4,44,54,64,74,84 Inner frame 4a, 44a, 54a, 64a, 74a, 84a Extension part 5 Liquid crystal display panel 6 Transparent joining Material 7 Transparent protective plate 8 Light shielding layer 9 Bonding material 11 Frame 11a Side wall 11b Through hole 11c Collar 11d Projection G1 First gap G2 Second gap G3 Third gap G4 Fourth gap

Claims (6)

  A concave container whose one end is an open end, a backlight device placed on the bottom surface of the container, and a collar portion extending inside the container in plan view and covering the open end of the container A frame body whose side wall portion is locked to a locking portion of the side wall of the container, an inner frame body positioned at an end portion of the bottom surface of the container, and a central portion of the surface on the backlight device side is a liquid crystal display panel A liquid crystal display device having a transparent protective plate joined thereto, wherein the liquid crystal display panel has a first gap between the backlight device and the frame body in plan view. The opening formed by the collar portion is outside the outer shape of the liquid crystal display panel and has a second gap between the collar portion and the transparent protective plate, and the inner frame body With a third gap between the side of the light device and The first has an extending portion that enters into the gap, a liquid crystal display device and the peripheral portion of the said extending portion liquid crystal display panel is bonded by bonding material.   The liquid crystal display device according to claim 1, wherein the collar portion has a protrusion on a surface facing the transparent protective plate.   The liquid crystal display device according to claim 1, wherein the inner frame has a fourth gap between the inner frame and the flange.   The inner frame has a recess for reducing a contact area on at least one of a surface in contact with an end of the bottom surface of the container and a surface on the collar side. A liquid crystal display device according to claim 1.   The said transparent protective board has a light shielding layer in the peripheral part of the surface at the side of the said backlight apparatus from the peripheral part of the said liquid crystal display panel to the said collar part. Liquid crystal display device.   The liquid crystal display device according to any one of claims 1 to 5, wherein a thickness of a bonding material for bonding the liquid crystal display panel and the transparent protective plate is 0.3 mm or less.