JP2014044304A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device in which the unevenness of luminance is not generated in an image displayed on a liquid crystal panel, by preventing the deformation of a light guiding plate.SOLUTION: A liquid crystal display device 10 is constituted of: a liquid crystal panel 18; and a backlight device 10a for illuminating the liquid crystal panel 18 from its rear face. The backlight device 10a includes: a circuit board 12; an LED 11 disposed on a front face of the circuit board 12; a plate 13 disposed on the lateral side of the LED 11 on the front face of the circuit board 12, and constituting a surface in a position spaced upward from the circuit board 12; a light guiding plate 16; and a cushioning material 14. The light guiding plate 16 is constituted of: a plate-like light guiding plate body 16a disposed on the rear face of the liquid crystal panel 18; and a light receiving part 16b extending from the light guiding plate body 16a toward the LED 11, and the cushioning material 14 is disposed between the plate 13 and the light guiding plate body 16a.

Description

  The present invention relates to a liquid crystal display device including a liquid crystal panel and a backlight device that illuminates the liquid crystal panel from the back surface.

  Conventionally, a liquid crystal display device is used as a display for a vehicle, a screen of a mobile phone, or the like. Such a liquid crystal display device is provided with a liquid crystal panel and a backlight device that illuminates the liquid crystal panel from the back side. A light guide plate that irradiates the back surface of the liquid crystal panel by receiving incident light and guiding it, and various plate members are laminated. Among liquid crystal display devices, there is a liquid crystal display device in which a light guide plate, a plate, or the like is not rattled using a buffer material (see, for example, Patent Document 1).

  In this liquid crystal display device, a reflection sheet, a light guide plate, and an optical film are laminated on a plate (resin frame), and a circuit board (wiring board) on which a light source is arranged is provided on the side of the light guide plate to provide a backlight device. (Backlight) is configured. And this backlight apparatus is mounted | worn in the box-shaped exterior part, and is being fixed in the exterior part by attaching a mounting frame to the upper part of an exterior part. Further, a buffer material (buffer member) is provided between the bottom upper surface of the exterior portion and the lower surface of the plate, between the inner side surface of the exterior portion and the side surface of the plate, and between the inner side surface of the exterior portion and the back surface of the circuit board. Is installed to prevent rattling of each part.

JP 2007-248820 A

  However, in the above-described conventional liquid crystal display device, since the cushioning material installed between the bottom upper surface of the exterior part and the lower surface of the plate locally abuts the plate, the plate and the light guide plate are likely to be deformed. . As a result, the refractive index of the light passing through the light guide plate changes, and a portion with high luminance may be locally generated in an image displayed on the liquid crystal panel. In the conventional liquid crystal display device described above, since the circuit board is small, it can be arranged on the side of the light guide plate. However, if this circuit board is large, the light guide plate and the plate In a state where they are laminated together, they are arranged below the plate. In this case, it becomes difficult to install the circuit board due to the buffer material.

  The present invention has been made to address the above problems, and an object of the present invention is to provide a liquid crystal display device that prevents the light guide plate from being deformed and does not cause uneven brightness in an image displayed on the liquid crystal panel. Is to provide. In the description of each constituent element of the present invention below, the reference numerals of corresponding portions of the embodiment are shown in parentheses in order to facilitate understanding of the present invention. The present invention should not be construed as being limited to the configurations of the corresponding portions indicated by the reference numerals of the forms.

  In order to achieve the above object, the liquid crystal display device according to the present invention is characterized in that a liquid crystal display device (18) and a backlight device (10a) for illuminating the liquid crystal panel from the back surface ( 10) a circuit board (12) having electronic components (12a, 12b) mounted on the surface thereof, a light source (11) installed on the surface of the circuit board, and an upward direction from the circuit board. A plate (13) installed on the front surface of the circuit board, a plate-shaped main body (16a) disposed on the back surface of the liquid crystal panel, and a main body extending from the main body toward the light source in order to form a surface at a separated position A light guide plate (16) including a light receiving portion (16b) and a plate-like cushioning material (14) disposed between the plate and the main body of the light guide plate are provided.

  In the liquid crystal display device according to the present invention, the buffer material is constituted by a plate-like member, and is disposed between the plate formed in a plate shape and the main body of the light guide plate. For this reason, even if a force in the thickness direction is applied to the laminated circuit board, plate, light guide plate main body, and liquid crystal panel, each member, in particular, the light guide plate main body adjacent to the buffer material is not deformed. This prevents uneven brightness from occurring in the image displayed on the liquid crystal panel. Further, since the buffer material is deformed in the thickness direction, errors in the thickness direction of the backlight device are absorbed, so that the light guide plate and the plate are maintained in an appropriate state between the circuit board and the liquid crystal panel.

  In addition, the plate-shaped cushioning material in the present invention is not limited to a complete plate-shaped member, and may be a material in which holes are partially provided, a lattice shape, a frame shape, or the like. In short, even if pressed by the plate and the main body of the light guide plate, the plate and the main body of the light guide plate, in particular, a plane that does not cause deformation by applying a local force to the main body of the light guide plate may be provided. . For this reason, even if a hole or the like is formed in the cushioning material, it is preferable to make the hole as small as possible. Note that to form a surface at a position spaced upward from the circuit board means to form a predetermined space between the surface of the circuit board and the plate.

  Another structural feature of the liquid crystal display device according to the present invention is that the size of the cushioning material in the surface direction is set substantially equal to that of the main body of the light guide plate. According to the present invention, the size of the buffer material and the light guide plate main body in plan view are substantially the same, so that the entire light guide plate main body is not deformed while minimizing the size of the buffer material. Can do. In addition, the liquid crystal display device can be prevented from becoming large in the horizontal direction.

  Still another structural feature of the liquid crystal display device according to the present invention is that the size of the cushioning material in the surface direction is set substantially equal to that of the plate. According to the present invention, since the size of the cushioning material and the plate in a plan view is substantially the same, it is possible to prevent deformation of the entire plate while minimizing the size of the cushioning material. This also prevents the liquid crystal display device from becoming large in the horizontal direction.

  Still another structural feature of the liquid crystal display device according to the present invention is that a recess (13c) capable of accommodating an electronic component is provided on the surface of the plate facing the circuit board. According to the present invention, since the height of the electronic component is absorbed by the thickness of the plate, the liquid crystal display device can be thinned by the depth of the recess. In addition, the recessed part formed in the plate in this case may be a recessed part surrounded by a wall part, or may be a recessed part formed by providing column parts at the four corners of the flat part.

  Still another structural feature of the liquid crystal display device according to the present invention is that the electronic component includes at least one large electronic component (12b), and the large electronic component is inserted into a portion of the plate facing the large electronic component. The through hole (13d) is provided. According to the present invention, when a small electronic component is included in the electronic component, the small electronic component can be positioned in the concave portion of the plate having the ceiling portion, and the upper portion of the large electronic component can be positioned in the through hole. Therefore, even when a small electronic component and a large electronic component are installed on the circuit board, the total thickness of the circuit board and the plate can be kept constant. In addition, since the buffer material is located between the plate and the main body of the light guide plate, the buffer material prevents light passing through the main body of the light guide plate from being radiated to the outside from the through hole of the plate. . In addition, when the hole is provided in the shock absorbing material, the position of the hole and the position of a through-hole are made different.

  Still another structural feature of the liquid crystal display device according to the present invention is that a gap is provided between the circuit board and the light receiving portion of the light guide plate. According to the present invention, the light guide plate is prevented from being stressed by being in contact with the circuit board. Thereby, it can prevent that durability of a light-guide plate falls because a light-receiving part contact | abuts to a circuit board.

  Still another structural feature of the liquid crystal display device according to the present invention is that a gap is provided between the light source and the light receiving portion of the light guide plate. According to the present invention, the light guide plate is prevented from being stressed or heated by contacting the light source. This can prevent the durability of the light guide plate from decreasing. For example, when the light guide plate is made of silicon resin and the light receiving portion is brought into contact with the light source, the light guide plate is likely to deteriorate because repeated stress is applied in a heated state. By providing a gap between them, such deterioration does not occur. Moreover, it can prevent that a light source is damaged by contact | abutting to a light-receiving part.

  Still another structural feature of the liquid crystal display device according to the present invention is that the light guide plate is formed of a molded body of a hard resin. According to the present invention, since the light guide plate is difficult to deform, the light received from the light source can be guided in an appropriate state to irradiate the liquid crystal panel. In this case, the hard resin is a resin having such a hardness that it does not deform even when a compressing force is applied in the thickness direction.

It is sectional drawing which showed the principal part of the liquid crystal display device which concerns on one Embodiment of this invention. The circuit board is shown, (a) is the perspective view seen from the upper surface side, (b) is the perspective view seen from the lower surface side. The plate is shown, (a) is the perspective view seen from the upper surface side, (b) is the perspective view seen from the lower surface side. It is the perspective view which showed the buffer material. It is the perspective view which showed the reflecting plate. It is the perspective view which showed the light-guide plate. It is the perspective view which showed the diffusion plate. It is the perspective view which showed the liquid crystal panel. It is the perspective view which showed the rubber connector. It is the perspective view which showed the outer case.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a cross section of the main part of the liquid crystal display device 10 according to the embodiment. The liquid crystal display device 10 is used, for example, by being attached to a handle of an electrically assisted bicycle, and values indicating traveling speed, remaining battery capacity, calorie consumption, etc. are displayed on a screen provided on the surface. In the liquid crystal display device 10, a plate 13, a buffer material 14, a reflecting plate 15, a light guide plate 16, a diffusion plate 17, and a liquid crystal panel 18 are sequentially arranged in the center of the upper surface of the circuit board 12 on which the LEDs 11 are installed near the edge of the upper surface. The circuit board 12 and the liquid crystal panel 18 are laminated and connected by a rubber connector 19 (see FIG. 9), and the whole is covered with an outer case 21.

  As shown in FIGS. 2A and 2B, the circuit board 12 is formed in a substantially rectangular flat plate shape in which the four corners of the rectangle are arcuate, and a circuit (not shown) is formed on the upper surface. A plurality of small electronic components 12a and large electronic components 12b are installed in the predetermined portion. In addition, an electrode 12c is provided to which the lower part of the rubber connector 19 is connected along one longitudinal edge of the upper surface of the circuit board 12, and a plurality of switches 12d are provided near the peripheral edge of the lower surface of the circuit board 12. Is provided. Further, in the vicinity of the peripheral edge of the circuit board 12, an attachment hole 12 e for attaching another member to the upper surface of the circuit board 12 is provided. A power source is connected to a predetermined portion of the circuit board 12 via wiring.

  The LED 11 is a top view type LED that emits light upward, and is installed near one edge on the upper surface of the circuit board 12. The LED 11 is connected to a circuit formed on the upper surface of the circuit board 12 via wiring, and is supplied with power through the wiring to emit light. The LED 11 constitutes a light source according to the present invention.

  The plate 13 is composed of a member made of a plate-shaped resin material having a substantially rectangular shape in plan view, which is installed on the upper surface of the circuit board 12 while protecting the small electronic component 12a and the large electronic component 12b. And as shown to Fig.3 (a), (b), the plate 13 is provided with the ceiling part 13a and the peripheral wall part 13b with the low height which protruded below from the peripheral part of the ceiling part 13a. For this reason, a shallow concave portion 13 c is formed at the center of the lower surface of the plate 13, and a certain gap is provided between the ceiling portion 13 a and the upper surface of the circuit board 12. Moreover, a plurality of rectangular through holes 13d penetrating vertically are formed in the ceiling portion 13a.

  A support portion 13 e for supporting the rubber connector 19 is formed on one side portion along the longitudinal direction of the plate 13. The support portion 13e is configured by providing a substantially L-shaped projection in plan view on both sides of one side portion in the longitudinal direction of the plate 13 and forming a recess between the projections. A support piece is formed at the tip of the plate so as to extend upward. When the plate 13 is installed on the upper surface of the circuit board 12, the lower surface of the peripheral wall portion 13b comes into contact with the upper surface of the circuit board 12, and the small electronic component 12a is positioned below the ceiling portion 13a, and the large electronic component 12b. Is in a state where the upper portion is located inside the through hole 13d.

  The buffer material 14 is formed of a molded body made of black foamed urethane, and is formed in a rectangular sheet shape as shown in FIG. The cushioning material 14 is formed to be approximately the same size as the portion of the plate 13 excluding the support portion 13e, and is installed on the upper surface of the ceiling portion 13a of the plate 13 with the through hole 13d closed. Moreover, the thickness of the buffer material 14 is set to 1.2 mm. A polycarbonate reflector 15 is provided on the upper surface of the buffer material 14. As shown in FIG. 5, the reflector 15 is formed in a shape in which a circular protrusion 15 a for preventing displacement with a hole formed in the center is protruded at one corner of a rectangular thin sheet, It is colored cloudy. For this reason, when light is irradiated from the upper surface side, the light is reflected to prevent the light from proceeding to the buffer material 14 side.

  The light guide plate 16 is formed of a plate-shaped molded body made of transparent polycarbonate, and includes a light guide plate body 16a and a light receiving portion 16b as shown in FIG. The light guide plate main body 16a is formed in a rectangular flat plate shape having a size in plan view that is substantially the same as that of the cushioning material 14, and the light receiving portion 16b extends obliquely downward from one edge of the light guide plate main body 16a. It is formed in a low plate shape that bends and extends downward. The light guide plate 16 is installed in a state where the light guide plate main body 16 a is installed on the upper surface of the reflecting plate 15 and the lower end portion of the light receiving unit 16 b is opposed to the upper surface of the LED 11. In addition, a gap is formed between the lower end surface of the light receiving unit 16b, the circuit board 12, and the upper surface of the LED 11. The light guide plate 16 is made of a hard material having a thickness set to 1.6 mm, and is configured not to be deformed by a force applied to the light guide plate 16 during normal use.

  The diffuser plate 17 is made of a polycarbonate translucent sheet that is the same shape as the reflector plate 15 and is colored in blue. As shown in FIG. 7, a hole is formed in the center at one corner. A circular protrusion 17a for preventing displacement is formed. The diffusing plate 17 has a function of making the whole light uniform by scattering and diffusing light guided by the light guide plate 16. Note that the reflecting plate 15 and the diffusing plate 17 are each formed in a thin sheet shape and are likely to be displaced, and thus provided with a protrusion 15a and a protrusion 17a for preventing the displacement. The liquid crystal panel 18 includes a glass substrate, a liquid crystal, a color filter, and the like. As shown in FIG. 8, an electrode 18 a to which the upper portion of the rubber connector 19 is connected is provided at a portion facing the electrode of the circuit board 12. Is provided. The liquid crystal panel 18 displays an image corresponding to a signal sent from the circuit board 12 via the rubber connector 19.

  The rubber connector 19 is formed in a square plate shape by covering a plurality of conductive parts with non-conductive rubber, and the conductive parts are exposed at the upper part and the lower part. In the state shown in FIG. 9, the rubber connector 19 is formed in a rectangular shape that is long in the left-right direction, short in the up-down direction, and further shortened in the front-rear thickness, and the conductive portion is inside the non-conductive rubber. It extends vertically. The rubber connector 19 is sandwiched between the circuit board 12 and the liquid crystal panel 18 with the lower end portion of the conductive portion in contact with the electrode 12 c of the circuit board 12 and the upper end portion of the conductive portion in contact with the electrode 18 a of the liquid crystal panel 18. In this state, the side portion is supported by the support portion 13 e of the plate 13.

  As shown in FIG. 10, the outer case 21 includes a ceiling portion 21a and a peripheral wall portion 21b that protrudes downward from the peripheral edge portion of the ceiling portion 21a. A rectangular window portion is provided at the center of the ceiling portion 21a. 21c is formed. A transparent lens 22 is attached to the window portion 21c. In addition, a cylindrical boss 21d and a rod-shaped positioning projection 21e are formed around the lens 22 on the lower surface of the ceiling portion 21a. As described above, the outer case 21 is assembled to the circuit board 12 with the plate 13 and the like laminated on the upper surface of the circuit board 12 covered and fixed from above.

  At that time, the boss 21d is used to fix the outer case 21 to the circuit board 12 via screws (not shown), and the positioning protrusion 21e is formed in the hole of the protrusion 15a of the reflecting plate 15 and the diffusion plate 17. The holes of the projections 17a are inserted so that the reflecting plate 15 and the diffusing plate 17 are not displaced. Further, by fixing the outer case 21 to the circuit board 12, a force to compress vertically is applied to the stacked plates 13 and the like. However, since the thickness is changed by the deformation of the cushioning material 14, The light guide plate 16 and the like are maintained in an appropriate state without deformation.

  And when the buffer material 14 deform | transforms, since the clearance gap is provided between LED11 and the light-receiving part 16b of the light-guide plate 16, the light-receiving part 16b is not pressed against LED11. In addition, the liquid crystal panel 18 is positioned at the window 21 c of the outer case 21, and an image displayed on the liquid crystal panel 18 can be seen from the outside through the lens 22. The LED 11, the circuit board 12, the plate 13, the buffer material 14, the reflection plate 15, the light guide plate 16, and the diffusion plate 17 constitute the backlight device 10 a according to the present invention.

  The body of an electrically assisted bicycle is equipped with various devices such as a speed sensor that detects the running speed, a measuring device that measures the remaining amount of the battery, a rotation sensor that detects the amount of rotation of the pedal, and a power source. These devices are connected to the circuit board 12 through wiring. For this reason, the liquid crystal display device 10 can receive signals from a speed sensor or the like and display values corresponding to those signals.

  In this configuration, when the liquid crystal display device 10 displays an image, first, the LED 11 emits light upward. The light enters the light receiving portion 16b from the lower end surface of the light receiving portion 16b of the light guide plate 16 facing the LED 11, and is further guided into the light guide plate body 16a. In that case, since the clearance gap is provided between LED11 and the lower end surface of the light-receiving part 16b, the light-receiving part 16b is hardly influenced by the heat | fever of LED11. The light passing through the light guide plate main body 16a is prevented from traveling downward by the reflecting plate 15 disposed on the lower surface of the light guide plate main body 16a, and can only travel upward.

  The light emitted upward from the light guide plate main body 16a is scattered and diffused by the diffusion plate 17 to have a uniform brightness, and becomes bluish light and irradiates the back surface of the liquid crystal panel 18. Further, predetermined numerical values and the like are formed on the liquid crystal panel 18 as an image, and this image is clearly displayed by the bluish light from the backlight device 10a.

  As described above, in the liquid crystal display device 10 according to the present embodiment, the buffer material 14 is configured by a plate-shaped molded body made of urethane foam, and is disposed between the upper surface of the plate 13 and the light guide plate body 16a. . For this reason, even if force in the thickness direction is applied to the laminated circuit board 12, plate 13, reflector 15, light guide plate 16, diffusing plate 17 and liquid crystal panel 18, no deformation occurs in each member. This prevents uneven brightness from occurring in the image displayed on the liquid crystal panel 18. That is, since the buffer material 14 is deformed in the thickness direction, an error in the thickness direction of the backlight device 10a is absorbed, so that the light guide plate 16 and the plate 13 are maintained in an appropriate state.

  In the liquid crystal display device 10, a recess 13 c is provided on the surface of the plate 13 that faces the circuit board 12, and a through hole 13 d is provided in a portion of the plate 13 that faces the large electronic component 12 b. For this reason, the small electronic component 12a can be positioned in the recess 13c, and the upper portion of the large electronic component 12b can be positioned in the through-hole 13d. This makes it possible to reduce the thickness of the entire liquid crystal display device 10. Further, since the cushioning material 14 is located between the plate 13 and the light guide plate main body 16a, the light passing through the light guide plate main body 16a is not radiated to the outside from the through hole 13d of the plate 13.

  In the liquid crystal display device 10, a gap is provided between the LED 11 and the lower end surface of the light receiving unit 16b. For this reason, contact with the LED 11 prevents the light guide plate 16 from being stressed or heated, and the durability of the light guide plate 16 can be improved. Further, the contact with the light guide plate 16 prevents the LED 11 from being damaged. Furthermore, since the light guide plate 16 is formed of a hard polycarbonate molded body, it is difficult to deform, and the light received from the LED 11 can be guided in an appropriate state to irradiate the liquid crystal panel 18. Moreover, since the plate 13, the buffer material 14, and the light guide plate main body 16 a have substantially the same size in plan view, the size can be minimized in the stacked state, and the liquid crystal display device 10 can be made compact. it can.

  The liquid crystal display device 10 according to the present invention is not limited to the above-described embodiment, and can be appropriately changed within the technical scope of the present invention. For example, in the above-described embodiment, the light source is configured by the top view type LED 11, but a side view type LED may be used as the light source. In this case, the light guide plate is formed so that the front end surface of the light receiving portion faces the LED oriented in the horizontal direction. Also in this case, a gap is provided between the front end surface of the light receiving unit and the LED, and a gap is also formed between the light receiving unit and the circuit board. As a result, the light receiving unit does not interfere with the LED or the circuit board.

  Moreover, in embodiment mentioned above, although the shock absorbing material 14 is comprised with foaming urethane, as this shock absorbing material, if it can shape | mold into the sheet form provided with cushioning properties not only foaming urethane, other cushioning material will be mentioned. Materials may be used. Furthermore, the light guide plate 16 is not limited to polycarbonate, but may be composed of other resin materials such as acrylic resin or silicon resin. Similarly, the material constituting the reflecting plate 15 and the diffusing plate 17 may be a resin material other than polycarbonate. Further, in the embodiment described above, the cushioning material 14 is formed in a flat plate shape, but the cushioning material according to the present invention is not limited to a complete plate-shaped member, It may be in a lattice shape or the like, and if it is formed in a substantially flat plate shape as a whole, it is included in the plate-like cushioning material according to the present invention.

  Further, in the above-described embodiment, the outer peripheral portion of the plate 13 is configured by the peripheral wall portion 13b. However, column portions provided at the four corners of the ceiling portion 13a may be used instead of the peripheral wall portion 13b. In the above-described embodiment, the through hole 13d is provided in the portion of the plate 13 that faces the large electronic component 12b. However, the through hole 13d is not provided, and the concave portion 13c is deepened so that the large electronic component is formed in the concave portion 13c. 12b may be located. Furthermore, other portions of the liquid crystal display device 10 can be implemented with appropriate modifications within the technical scope of the present invention. In addition, the liquid crystal display device 10 according to the present invention can be provided not only in an electrically assisted bicycle but also in a motorcycle, an automobile, a bicycle, or the like.

  DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display device, 10a ... Backlight device, 11 ... LED, 12 ... Circuit board, 12a ... Small electronic component, 12b ... Large electronic component, 13 ... Plate, 13c ... Recessed part, 13d ... Through-hole, 14 ... Buffer material 16 light guide plate, 16 a light guide plate body, 16 b light receiving portion, 18 liquid crystal panel.

In this liquid crystal display device, the plate reflection sheet on the (resin frame), a light guide plate and the optical film are laminated on a side of the light guide plate, the circuit board (wiring board) which the light source is arranged set Ketaba backlight device (Backlight) is configured. And this backlight apparatus is mounted | worn in the box-shaped exterior part, and is being fixed in the exterior part by attaching a mounting frame to the upper part of an exterior part. Further, a buffer material (buffer member) is provided between the bottom upper surface of the exterior portion and the lower surface of the plate, between the inner side surface of the exterior portion and the side surface of the plate, and between the inner side surface of the exterior portion and the back surface of the circuit board. Is installed to prevent rattling of each part.

However, in the conventional liquid crystal display device described above is installed cushioning material between the lower surface of the bottom portion upper surface and the plate of the exterior portion, locally order to contact the plate, apt deformation occurs in the plate and the light guide plate Become. As a result, the refractive index of the light passing through the light guide plate changes, and a portion with high luminance may be locally generated in an image displayed on the liquid crystal panel. In the conventional liquid crystal display device described above, since the circuit board is small, it can be arranged on the side of the light guide plate. However, if this circuit board is large, the light guide plate and the plate In a state where they are laminated together, they are arranged below the plate. In this case, it becomes difficult to install the circuit board due to the buffer material.

To achieve the above objects, features on the configuration of the liquid crystal display device according to the present invention, a liquid crystal display device including a liquid crystal panel (18), the backlight device you irradiating a liquid crystal panel from the back and (10a) (10) comprising, in the installed backlights device on the back side of the liquid crystal panel, electronic parts on the surface (12a, 12b) and the circuit board mounted is (12), a light source placed on the surface of the circuit board ( and 11), with a predetermined space between the surface of the circuit board, a plate placed on the surface of the circuit board (13), installed on the surface of the plate a plate-like cushioning member (14) , electrically consisting back surface of the liquid crystal panel and arranged plate-like light guide board book material between the surface of the buffer material and (16a), a light receiving portion extending from the light guide board book body towards the light source (16b) The light plate (16) is provided.

In the liquid crystal display device according to the present invention is to constitute a cushioning material in a plate-like member, the cushioning material, and is placed between the monitor plate to form a plate and the light guide board book body . Thus, laminated circuit board, plate, light guide board book body and also the thickness direction of the force is applied to the liquid crystal panel members, particularly, the light guide board book bodies adjacent to the cushioning material, deformation does not occur . Thus, unevenness of brightness in images displayed on the liquid crystal panel is locked generated child Togabo. Further, since the buffer material is deformed in the thickness direction, errors in the thickness direction of the backlight device are absorbed, so that the light guide plate and the plate are maintained in an appropriate state between the circuit board and the liquid crystal panel.

In addition, the plate-shaped cushioning material in the present invention is not limited to a complete plate-shaped member, and may be a material in which holes are partially provided, a lattice shape, a frame shape, or the like. In short, be pressed into the plate and the light guide board book body plate and the light guide board book body, in particular, it is deformed by adding a local force to the light guide board book body provided with a plane that does not occur Just do it. For this reason, even if a hole or the like is formed in the cushioning material, it is preferable to make the hole as small as possible .

Another structural feature of the liquid crystal display device according to the present invention, a large can of a plane view of the cushioning material is that it is set to substantially equal to the size of a plane view of the light guide plate body. According to the present invention, since the size of the buffer material and the light guide board book body according plan view becomes substantially the same, be made to deform the whole of the light guide board book body does not occur while the cushioning material to a minimum it can. In addition, the liquid crystal display device can be prevented from becoming large in the horizontal direction.

Further structural features of the liquid crystal display device according to the present invention, a large can of a plane view of the cushioning material is that it is set to a size substantially equal to a plane view of the plate. According to the present invention, since the size of the cushioning material and the plate in a plan view is substantially the same, it is possible to prevent deformation of the entire plate while minimizing the size of the cushioning material. This also prevents the liquid crystal display device from becoming large in the horizontal direction.

Still another structural feature of the liquid crystal display device according to the present invention is that the electronic component includes at least one large electronic component (12b), and the large electronic component is inserted into a portion of the plate facing the large electronic component. The through hole (13d) is provided. According to the present invention, when a small electronic component is included in the electronic component, the small electronic component can be positioned in the concave portion of the plate having the ceiling portion, and the upper portion of the large electronic component can be positioned in the through hole. Therefore, even when a small electronic component and a large electronic component are installed on the circuit board, the total thickness of the circuit board and the plate can be kept constant. The prevention, between the plate and the light guide board book body, since the buffer member is located, the light passing through the light guide board book body is radiated to the outside from the through hole of the plate by cushioning material Is done. In addition, when the hole is provided in the shock absorbing material, the position of the hole and the position of a through-hole are made different.

Further structural features of the liquid crystal display device according to the present invention is that the gap is provided between the light receiving portion of the surface and the light guide plate of the circuit board. According to the present invention, by Rukoto to contact the surface of the circuit board, stress in the light guide plate can take is prevented. This can prevent the light receiving portion by Rukoto to contact the surface of the circuit board, the durability of the light guide plate is reduced.

Still another structural feature of the liquid crystal display device according to the present invention is that a gap is provided between the light source and the light receiving portion of the light guide plate. According to the present invention, by Rukoto to contact the light source, the stress in the light guide plate that is suffering or heat is applied or is prevented. This can prevent the durability of the light guide plate from decreasing. For example, when the light guide plate is made of silicon resin and the light receiving portion is brought into contact with the light source, the light guide plate is likely to deteriorate because repeated stress is applied in a heated state. By providing a gap between them, such deterioration does not occur. Further, it is also prevented that the light source by Rukoto be in contact with the light-receiving portion is damaged.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a cross section of the main part of the liquid crystal display device 10 according to the embodiment. The liquid crystal display device 10 is used, for example, by being attached to a handle of an electrically assisted bicycle, and values indicating traveling speed, remaining battery capacity, calorie consumption, etc. are displayed on a screen provided on the surface . In the following description of the embodiment, the vertical direction is based on FIG. 1, and the upper side in FIG. 1 is the upper side and the lower side is the lower side. Furthermore, the front surface according to the present invention is an upper surface, and the back surface according to the present invention is a lower surface. That is, in the following embodiments, the front surface according to the present invention is a surface located above each member constituting the liquid crystal display device 10, and the back surface side according to the present invention is below each member constituting the liquid crystal display device 10. It becomes the surface located at. The liquid crystal display device 10 of this is the center of the upper surface of the circuit board 12 LED11 near the edge of the top surface is installed, the plate 13, cushioning member 14, the reflecting plate 15, the light guide plate 16, the diffusion plate 17 and the liquid crystal panel 18 The circuit board 12 and the liquid crystal panel 18 are sequentially stacked and connected with a rubber connector 19 (see FIG. 9), and the whole is covered with an outer case 21.

As shown in FIGS. 2A and 2B, the circuit board 12 is formed in a substantially rectangular flat plate shape in which the four corners of the rectangle are arcuate, and a circuit (not shown) is formed on the upper surface. A plurality of small electronic components 12a and large electronic components 12b are installed in the predetermined portion. The electrode 12c for the lower portion of the rubber connector 19 is connected is provided along one edge of the longitudinal direction of the upper surface of the circuit board 12, the other near the edge of the longitudinal direction that put the lower surface of the circuit board 12 Are provided with a plurality of switches 12d. Further, an attachment hole 12 e for attaching another member to the upper surface of the circuit board 12 is provided in the vicinity of one edge in the short direction on the upper surface of the circuit board 12. The predetermined unit amount of the circuit board 12 is connected to power via the wiring.

LED11 is an LED of the top view type for irradiating light toward the upper direction from the upper surface, are disposed near the edge of the hand in the transverse direction that put on the upper surface of the circuit board 12. The LED 11 is connected to a circuit formed on the upper surface of the circuit board 12 via wiring, and is supplied with power through the wiring to emit light. The LED 11 constitutes a light source according to the present invention.

The plate 13 is composed of a member made of a plate-shaped resin material having a substantially rectangular shape in plan view, which is installed on the upper surface of the circuit board 12 while protecting the small electronic component 12a and the large electronic component 12b. And as shown to Fig.3 (a), (b), the plate 13 is provided with the ceiling part 13a and the peripheral wall part 13b with the low height which protruded below from the peripheral part of the ceiling part 13a. For this reason, a shallow recess 13 c is formed at the center of the lower surface of the plate 13, and a certain gap is provided between the lower surface of the ceiling portion 13 a and the upper surface of the circuit board 12. Moreover, a plurality of rectangular through holes 13d penetrating vertically are formed in the ceiling portion 13a.

Then, in one of the longitudinal direction along a portion of Plate 13 in the peripheral wall portion 13b, the support portions 13e for supporting the rubber connector 19 is formed. The supporting portion 13e is to form a recess between the projections arranged to face the projection plan view of a substantially L-shape on opposite sides of one of portions along the longitudinal direction of Plate 13 in the peripheral wall 13b A support piece is formed at the tip of both protrusions so as to extend upward. When the plate 13 is installed on the upper surface of the circuit board 12, the lower surface of the peripheral wall portion 13b is in contact with the upper surface of the circuit board 12, and the small electronic component 12a is positioned below the ceiling portion 13a, and the large electronic component 12b. Is in a state where the upper portion is located inside the through hole 13d.

The buffer material 14 is formed of a molded body made of black foamed urethane, and is formed in a rectangular sheet shape as shown in FIG. The cushioning material 14 is formed to be approximately the same size as the portion of the plate 13 excluding the support portion 13e, and is installed on the upper surface of the ceiling portion 13a of the plate 13 with the through hole 13d closed. Moreover, the thickness of the buffer material 14 is set to 1.2 mm. A polycarbonate reflector 15 is provided on the upper surface of the buffer material 14. Reflector 15, as shown in FIG. 5, on one corner of the rectangular thin sheet, the center is formed in a shape obtained by projecting the collision force 15a for circular holes formed displacement prevention , It is colored cloudy. Therefore, when light is irradiated from the upper surface side, and reflects the light, light is prevented that you transmitted into the buffer material 14 side.

The light guide plate 16 is formed of a plate-shaped molded body made of transparent polycarbonate, and includes a light guide plate body 16a and a light receiving portion 16b as shown in FIG. The light guide plate main body 16a is formed in a rectangular flat plate shape having a size in plan view that is substantially the same as that of the buffer material 14, and the light receiving portion 16b extends obliquely downward from one edge of the light guide plate main body 16a. It is formed in a low plate shape that bends and extends downward. The light guide plate 16 is installed in a state where the light guide plate main body 16 a is installed on the upper surface of the reflecting plate 15 and the lower end portion of the light receiving unit 16 b is opposed to the upper surface of the LED 11. In addition, a gap is formed between the lower end surface of the light receiving unit 16b and the upper surfaces of the circuit board 12 and the LED 11. The light guide plate 16 has a thickness of 1 . It is made of a hard material set to 6 mm and is configured not to be deformed by a force applied to the light guide plate 16 during normal use.

The diffuser plate 17 is made of a polycarbonate translucent sheet that is the same shape as the reflector plate 15 and is colored blue. As shown in FIG. 7, a circular hole is formed in the center at one corner. been collision caused 17a for preventing displacement is formed. The diffusing plate 17 has a function of making the whole light uniform by scattering and diffusing light guided by the light guide plate 16. Note that a reflective plate 15 and the diffusion plate 17, and is easily respective thin formed into a sheet position deviation occurs, are provided projections 15a and projection 17a for preventing displacement. The liquid crystal panel 18, a glass substrate, a liquid crystal, have become the color filter, etc., to a portion facing the electrodes 12c of the circuit board 12, as shown in FIG. 8, electrode upper portion of the rubber connector 19 is connected 18a is provided. The liquid crystal panel 18 displays an image corresponding to a signal sent from the circuit board 12 via the rubber connector 19.

The rubber connector 19 is formed in a square plate shape by covering a plurality of conductive parts with non-conductive rubber, and the conductive parts are exposed at the upper part and the lower part. In the state shown in FIG. 9, the rubber connector 19 is formed in a shape that is long in the left-right direction, short in the up-down direction, and further shortened in the front-rear thickness, and the conductive portion is inside the non-conductive rubber. It extends vertically. The rubber connector 19 is sandwiched between the circuit board 12 and the liquid crystal panel 18 such that the lower end portion of the conductive portion is in contact with the electrode 12 c of the circuit board 12 and the upper end portion of the conductive portion is in contact with the electrode 18 a of the liquid crystal panel 18. In this state, the side portion is supported by the support portion 13 e of the plate 13.

At that time, the boss 21d is used to fix the outer case 21 to the circuit board 12 via screws (not shown), and the positioning protrusion 21e is formed in the hole of the protrusion 15a of the reflecting plate 15 and the diffusion plate 17. The holes of the projections 17a are inserted so that the reflecting plate 15 and the diffusing plate 17 are not displaced. Further, by fixing the outer casing 21 to the circuit board 12, the like plates 13 are laminated, a force to compress the up and down direction is applied, to change the thickness by the cushioning member 14 is deformed, the plate 13 and the light guide plate 16 and the like are maintained in an appropriate state without deformation.

In this configuration, when the liquid crystal display device 10 displays an image, first, the LED 11 emits light upward. The light enters the light receiving portion 16b from the lower end surface of the light receiving portion 16b of the light guide plate 16 facing the LED 11, and is further guided into the light guide plate body 16a. In that case, since the clearance gap is provided between LED11 and the lower end surface of the light-receiving part 16b, the light-receiving part 16b is hardly influenced by the heat | fever of LED11. The light passing through the light guide plate main body 16 a is the reflecting plate 15 disposed on the lower surface of the light guide plate body 16a, is prevented you to transmittance under side of the reflecting plate 15, above the light guide plate main body 16a toward it becomes irradiation available-in.

The light illuminates the upper side from the light guide plate main body 16a is by the diffusion plate 17, together with scattered and diffused by uniform brightness, illuminating the rear surface of the liquid crystal panel 18 becomes bluish light. Further, predetermined numerical values and the like are formed on the liquid crystal panel 18 as an image, and this image is clearly displayed by the bluish light from the backlight device 10a.

As described above, in the liquid crystal display device 10 according to the present embodiment, the buffer material 14 is configured by a plate-shaped molded body made of urethane foam, and is disposed between the upper surface of the plate 13 and the light guide plate body 16a. . For this reason, even if force in the thickness direction is applied to the laminated circuit board 12, plate 13, reflector 15, light guide plate 16, diffusing plate 17 and liquid crystal panel 18, no deformation occurs in each member. This prevents uneven brightness from occurring in the image displayed on the liquid crystal panel 18. That is, the buffer material 14 by deforming vertically Direction, since the upper and lower sides error of direction of the backlight device 10a is absorbed, the light guide plate 16 and plate 13 or the like is maintained in a proper state.

In the liquid crystal display device 10, a recess 13 c is provided on the surface of the plate 13 that faces the circuit board 12, and a through hole 13 d is provided in a portion of the plate 13 that faces the large electronic component 12 b. For this reason, the small electronic component 12a can be positioned in the recess 13c, and the upper portion of the large electronic component 12b can be positioned in the through-hole 13d. This makes it possible to reduce the thickness of the entire liquid crystal display device 10. Further, since the buffer material 14 and the reflecting plate 15 are located between the plate 13 and the light guide plate main body 16a, light passing through the light guide plate main body 16a is radiated to the outside from the through holes 13d of the plate 13. It will never be done.

In the liquid crystal display device 10, a gap is provided between the LED 11 and the lower end surface of the light receiving unit 16b. Therefore, by Rukoto light receiving portion 16b to contact the L ED11, it is prevented that stress in the light guide plate 16 is applied or is suffering or heat, it is possible to improve the durability of the light guide plate 16. Further, the Rukoto to contact the light guide plate 16 is also prevented from LED11 is damaged. Furthermore, since the light guide plate 16 is formed of a hard polycarbonate molded body, it is difficult to deform, and the light received from the LED 11 can be guided in an appropriate state to irradiate the liquid crystal panel 18. Moreover, since the plate 13, the buffer material 14, and the light guide plate main body 16 a have substantially the same size in plan view, the size can be minimized in the stacked state, and the liquid crystal display device 10 can be made compact. it can.

The liquid crystal display device 10 according to the present invention is not limited to the above-described embodiment, and can be appropriately changed within the technical scope of the present invention. For example, in the above-described embodiment, the light source is configured by the top view type LED 11, but a side view type LED may be used as the light source. In this case, the light guide plate is formed so that the front end surface of the light receiving portion faces the light emitting portion of the LED . Also in this case, a gap is provided between the front end surface of the light receiving unit and the LED, and a gap is also formed between the light receiving unit and the circuit board. As a result, the light receiving unit does not interfere with the LED or the circuit board.

Claims (8)

LCD panel,
A liquid crystal display device comprising a backlight device for illuminating the liquid crystal panel from the back surface,
In the backlight device,
A circuit board with electronic components mounted on the surface;
A light source installed on the surface of the circuit board;
A plate installed on the surface of the circuit board to form a surface at a position spaced upward from the circuit board;
A light guide plate comprising a plate-like main body disposed on the back surface of the liquid crystal panel, and a light receiving portion extending from the main body toward the light source;
A liquid crystal display device comprising a plate-shaped cushioning material disposed between the plate and the main body of the light guide plate.   The liquid crystal display device according to claim 1, wherein the size of the cushioning material in the surface direction is set to be substantially equal to that of the main body of the light guide plate.   3. The liquid crystal display device according to claim 1, wherein a size of the cushioning material in a surface direction is set to be substantially equal to that of the plate.   4. The liquid crystal display device according to claim 1, wherein a concave portion capable of accommodating the electronic component is provided on a surface of the plate facing the circuit board. 5.   The liquid crystal display according to claim 4, wherein the electronic component includes at least one large electronic component, and a through hole for inserting the large electronic component is provided in a portion of the plate facing the large electronic component. apparatus.   The liquid crystal display device according to claim 1, wherein a gap is provided between the circuit board and the light receiving portion of the light guide plate.   The liquid crystal display device according to claim 6, wherein a gap is provided between the light source and a light receiving portion of the light guide plate.   The liquid crystal display device according to claim 1, wherein the light guide plate is formed of a hard resin molding.

Images