JP2010039224A - Liquid crystal display device with shutter function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device with a shutter function, wherein more uniform lighting is available. <P>SOLUTION: The liquid crystal display device 100 with a shutter function includes: a transmissive liquid crystal display device 101 disposed on a position separated from an installation face 106; an liquid crystal shutter 102 disposed on the installation surface 106 side of the transmissive liquid crystal display device 101 and switching at least between a transparent state and a nontransparent state; a light source 103 disposed on the installation surface 106 side of the liquid crystal shutter 102 and placed along a periphery of the liquid crystal shutter 102; and a reflection member 104 surrounding the light source 103 and having a reflection surface 141 opened on the inner side, wherein the reflection surface 141 includes surfaces 142, 144 inclined toward the surface of the liquid crystal shutter 102 on the installation surface 106 side in a section vertical to the surface of the liquid crystal shutter 102 on the installation surface 106 side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device with a shutter function, and more particularly to a liquid crystal display device with a shutter function that can obtain more uniform illumination.

  As disclosed in Patent Document 1, a liquid crystal display device with a shutter function is known. In this case, a screen called a liquid crystal shutter, which can be switched between a transparent state and a cloudy and opaque state depending on whether or not an electric field is applied, is disposed on the rear surface of the transmissive liquid crystal display device. When such a liquid crystal display device with a shutter function is installed on a design-installed surface, only the screen of the transmissive liquid crystal display device can be seen when the liquid crystal shutter is opaque, and the transmissive liquid crystal display device when the liquid crystal shutter is transparent. The design of the installation surface can be visually recognized through this, and a novel visual expression can be provided.

  In such a liquid crystal display device with a shutter function, a light source such as a cold cathode tube and a reflective member having a reflective surface that surrounds the light source and is open on the inner side are disposed along the peripheral edge of the back surface of the liquid crystal shutter. Attempts have been made. FIG. 7 is a sectional view showing the structure of such a conventional liquid crystal display device 400 with a shutter function. The liquid crystal display device 400 with a shutter function has a structure in which a transmissive liquid crystal display device 401, a liquid crystal shutter 402, a cold cathode tube 403, and a reflection member 404 are attached to a frame 405. Then, the frame 405 is fixed to the installation surface 406. The installation surface 406 has a design surface 461 on which a design is applied.

In the liquid crystal display device 400 with a shutter function, the reflection surface 441 included in the reflection member 404 includes a near-side reflection surface 442, an outer reflection surface 443, and a far-side reflection surface 444, as illustrated. The outer reflection surface 443 is perpendicular to the surface on the installation surface 406 side of the liquid crystal shutter 402, and the near-side reflection surface 442 and the far-side reflection surface 444 are parallel to the surface on the installation surface 406 side of the liquid crystal shutter 402. .
JP 2005-65776 A

  In the conventional liquid crystal display device 400 with a shutter function shown in FIG. 7, the peripheral portion of the screen receives light from the cold cathode tube 403 and is bright, but the central portion of the screen is relatively dark, so the brightness of the entire screen is uniform. The problem of not being occurred.

  This invention is made | formed in view of this viewpoint, The objective is to provide the liquid crystal display device with a shutter function from which more uniform illumination is obtained.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  (1) A transmissive liquid crystal display device provided at a position separated from the installation surface, a liquid crystal shutter provided on the installation surface side of the liquid crystal display device and capable of switching at least between a transparent state and an opaque state, A light source provided on the installation surface side of the liquid crystal shutter and disposed along a peripheral edge of the liquid crystal shutter; and a reflective member having a reflective surface that surrounds the light source and is open on the inside. The liquid crystal display device with a shutter function, wherein the reflection surface includes a surface inclined with respect to the surface on the installation surface side of the liquid crystal shutter in a cross section perpendicular to the surface on the installation surface side of the liquid crystal shutter.

  (2) In (1), the inclined surface is inclined so as to move away from the surface on the installation surface side of the liquid crystal shutter in a direction perpendicular to the inner side toward the outer side. Liquid crystal display device.

  (3) In (1), the inclined surface is inclined so as to approach a direction perpendicular to the surface on the installation surface side of the liquid crystal shutter from the inside toward the outside. Liquid crystal display device.

  (4) In (1), the reflection surface is arranged on the outer reflection surface arranged outside the light source, and on the side closer to the liquid crystal shutter than the light source, and as the liquid crystal shutter moves from the inside toward the outside, The near-side reflecting surface that is inclined so as to move away from the surface on the installation surface side in a direction perpendicular to the surface, and is disposed closer to the installation surface than the light source, and the installation of the liquid crystal shutters from the inside toward the outside A liquid crystal display device with a shutter function, comprising: a far-side inclined surface that is inclined so as to approach a direction perpendicular to the surface-side surface.

  (5) In (1), the reflection surface is an outer reflection surface disposed outside the light source, and a near side that is disposed closer to the liquid crystal shutter than the light source and is substantially perpendicular to the outer reflection surface. A reflection surface, and a far-side reflection surface that is disposed closer to the installation surface than the light source and is substantially perpendicular to the outer reflection surface, and the near-side reflection surface and the far-side reflection surface are from the inside. A liquid crystal display device with a shutter function, wherein the liquid crystal display device is inclined so as to move away from the surface on the installation surface side of the liquid crystal shutter in a direction perpendicular to the outside.

  (6) In (1), the reflection surface is an outer reflection surface disposed outside the light source, and a near side that is disposed closer to the liquid crystal shutter than the light source and is substantially perpendicular to the outer reflection surface. A reflection surface, and a far-side reflection surface that is disposed closer to the installation surface than the light source and is substantially perpendicular to the outer reflection surface, and the near-side reflection surface and the far-side reflection surface are from the inside. A liquid crystal display device with a shutter function, wherein the liquid crystal display device is inclined so as to approach a direction perpendicular to the surface on the installation surface side of the liquid crystal shutter as it goes outward.

  According to the invention disclosed in the present application as described above, a liquid crystal display device with a shutter function capable of obtaining more uniform illumination can be provided.

  A preferred first embodiment of the present invention will be described below with reference to FIGS.

  FIG. 1 is a cross-sectional view showing the structure of a liquid crystal display device 100 with a shutter function according to the present embodiment.

  The liquid crystal display device 100 with a shutter function has substantially the same structure as the conventional liquid crystal display device 400 with a shutter function described above. That is, the transmissive liquid crystal display device 101 is provided apart from the installation surface 106, the liquid crystal shutter 102 is provided on the installation surface 106 side, and the cooling light source serving as a light source is provided on the installation surface 106 side along the peripheral edge of the liquid crystal shutter 102. A reflecting member 104 having a cathode tube 103 and a reflecting surface 141 surrounding the cold cathode tube 103 and opening inside is provided. Each member is attached to the frame 105, and the frame 105 is fixed to the installation surface 106.

  The installation surface 106 has a design surface 161 on which a design is applied. The installation surface 106 may be any type, for example, a gaming machine such as a pachinko machine or a slot machine, a vending machine, an instrument panel (instrument panel) of a passenger vehicle such as an automobile, a clock, an indoor interior The surface can be considered. Further, the design of the design surface 161 is not limited to a static one, and may be a dynamic one such as various measuring instruments or the hour hand surface of a timepiece.

  The transmissive liquid crystal display device 101 may be either color or monochrome, and the liquid crystal driving method is not limited. For example, any known method such as an IPS (In Plane Switching) method, a VA (Vertical Alignment) method, or a TN (Twisted Nematic) method may be used.

  The liquid crystal shutter 102 may be anything as long as it can switch at least between a transparent state and a cloudy and opaque state depending on whether or not an electric field is applied. As the mode of the liquid crystal shutter 102, either the normal mode or the reverse mode can be suitably used, but it may be selected according to the application. Further, by adjusting the electric field strength, it may be possible to make it translucent, or it may be able to transition continuously from a transparent state to an opaque state and vice versa.

  In the present embodiment, the cold cathode tube 103 is used for illumination, but is not limited thereto. A linear light source such as the cold cathode tube 103 is suitable, but a point light source such as an LED or a light bulb may be used. When using a point light source, a large number of point light sources may be arranged along the periphery of the liquid crystal shutter 102. Moreover, although what uses the cold cathode tube 103 by 2 sets is shown in figure, you may use only 1 piece or 3 or more pieces.

  As long as the frame 105 can support each member, the material, shape, and the like are not particularly limited. Although not shown, the frame 105 may incorporate a control circuit for operating the transmissive liquid crystal display device 101, the liquid crystal shutter 102, and the cold cathode tube 103. It may be supplied from the 106 side.

  The liquid crystal display device 100 with a shutter function is different from the conventional liquid crystal display device 400 with a shutter function in that the reflection surface 141 of the reflection member 104 has a shape that expands inward. That is, the reflective surface 141 is disposed on the outer reflective surface 143 disposed on the outer side of the cold cathode tube 103 and on the side closer to the liquid crystal shutter 102 than the cold cathode tube 103, and the liquid crystal shutter 102 is installed from the inner side toward the outer side. A near-side reflecting surface 142 that is inclined so as to be away from the surface on the surface 106 side, and a side closer to the installation surface 106 than the cold cathode tube 103, the liquid crystal shutter 102 It consists of a far-side inclined surface 144 that is inclined so as to approach a direction perpendicular to the surface on the installation surface 106 side.

  As described above, when the near-side reflection surface 142 is inclined from the inner side to the outer side so as to move away from the surface on the installation surface 106 side of the liquid crystal shutter 102 in the vertical direction, the light beam from the cold cathode tube 103 is As shown in a, it reaches the center of the design surface 161, so that more uniform illumination can be obtained mainly on the design surface 161.

  Further, when the far-side reflecting surface 144 is inclined from the inner side to the outer side so as to approach the vertical direction from the surface on the installation surface 106 side of the liquid crystal shutter 102, the light beam from the cold cathode tube 103 becomes b in the figure. As shown in the figure, it reaches the center of the liquid crystal shutter 102, so that the entire liquid crystal shutter 102 shines more uniformly in white, and more uniform illumination can be obtained mainly for the transmissive liquid crystal display device 101.

  As described above, the reflective surface 141 includes a surface that is inclined with respect to the surface on the installation surface 106 side of the liquid crystal shutter 102, so that more uniform illumination can be obtained.

  Furthermore, since the outer reflective surface 143 is substantially perpendicular to the surface on the installation surface 106 side of the liquid crystal shutter 102, the light rays from the cold cathode tube 103 can be evenly distributed to the design surface 161 and the liquid crystal shutter 102. .

  Note that the inclination angles of the near-side reflection surface 142 and the far-side reflection surface 144 from the surface parallel to the surface on the installation surface 106 side of the liquid crystal shutter 102 do not have to be equal. According to the color and brightness of the design surface 161, it is possible to appropriately adjust both the design surface 161 and the screen of the transmissive liquid crystal display device 101 so as to be easily visible.

  FIG. 2 is a diagram of the liquid crystal display device 100 with a shutter function according to the present embodiment as viewed from the installation surface 106 side. Portions hidden behind the reflecting member 104 are not shown for convenience of explanation.

  The cold cathode tube 103 is bent to the L-shaped side as shown in the figure, and the two are arranged so as to face each other. In this way, the liquid crystal shutters 102 are arranged along all four sides of the peripheral portion. Reference numeral 131 denotes a holder for fixing the cold cathode tube 103 and supplying power. Note that the cold cathode tube 103 is not limited to use as a set of two as shown here. A set of four, one on each side, may be used, or one bent to cover all four sides may be used. Further, the cold cathode tubes 103 are not necessarily arranged on all four sides, but may be arranged only on the upper and lower sides or the left and right sides.

  Next, a preferred second embodiment of the present invention will be described with reference to FIG.

  The liquid crystal display device with a shutter function 200 shown in the figure is different from the liquid crystal display device with a shutter function 100 according to the first embodiment only in the reflection member 204, and the others are the same. Will not be described.

  The reflecting member 204 in the present embodiment is configured such that the reflecting surface 241 is orthogonal to the outer reflecting surface 243 and the near-side reflecting surface 242 and the far-side reflecting surface 244 are orthogonal to each other. This is similar to the liquid crystal display device 400 with a shutter function. However, the difference is that the entire reflecting member 204 is disposed so as to be inclined toward the liquid crystal shutter 202 side. That is, the reflection surface 204 is disposed on the outer reflection surface 243 disposed outside the cold cathode tube 203, and is disposed on the side closer to the liquid crystal shutter 202 than the cold cathode tube 203, and the near-side reflection that is substantially perpendicular to the outer reflection surface 243. A near-surface reflecting surface 242 and a far-side reflecting surface 244 that are disposed on the side closer to the installation surface 206 than the cold cathode tube 203 and have a far-side reflecting surface 244 that is substantially perpendicular to the outer reflecting surface 243. Is inclined so as to move away from the surface on the installation surface 206 side of the liquid crystal shutter 202 in a direction perpendicular to the inner side toward the outer side.

  When the reflection surface 241 is arranged in this manner, a large amount of light from the cold cathode tube 203 can be collected by the liquid crystal shutter 202, so that the entire liquid crystal shutter 202 shines more uniformly white, and the screen of the transmissive liquid crystal display device 201 is more Visible clearly.

  The present embodiment can be suitably used when the screen of the transmissive liquid crystal display device 201 is relatively dark, such as the brightness of the design surface 261 is high.

  Furthermore, a preferred third embodiment of the present invention will be described with reference to FIG.

  The liquid crystal display device 300 with a shutter function shown in the figure is different from the liquid crystal display device 200 with a shutter function according to the second embodiment in that the reflection member 304 is entirely inclined toward the design surface 361 side. Since only the difference is the same and the others are the same, the description of the overlapping parts is omitted.

  That is, the reflecting surface 304 is disposed on the outer side of the cold cathode fluorescent lamp 303, and on the side closer to the liquid crystal shutter 302 than the cold cathode fluorescent lamp 303, and is reflected in the near side that is substantially perpendicular to the outer reflective surface 343. A near-side reflecting surface 342 and a far-side reflecting surface 344, which is disposed on the side closer to the installation surface 306 than the cold cathode tube 303 and has a far-side reflecting surface 344 that is substantially perpendicular to the outer reflecting surface 343. Is inclined so as to approach a direction perpendicular to the surface on the installation surface 306 side of the liquid crystal shutter 302 from the inside toward the outside.

  By disposing the reflection surface 341 in this way, a larger amount of light from the cold cathode tube 303 can be collected on the design surface 361, so that the entire design surface 361 can be illuminated more uniformly and the design surface 361 can be visually recognized more clearly.

  This embodiment can be suitably used when the brightness of the design surface 361 is low and the screen of the design surface 361 is relatively dark with respect to the screen of the transmissive liquid crystal display device 301.

  As an example, the liquid crystal display device 100 with a shutter function according to the first embodiment was produced, and the luminance distribution in the screen was measured.

  FIG. 5 is a diagram showing this embodiment.

  FIG. 4A is a cross-sectional view of the reflecting member 104 in the liquid crystal display device with a shutter function 100 according to the first embodiment produced as an example, and the unit of the numerical value in the drawing is mm. The reflecting surface was a white specular reflecting surface with a reflectance of 95%.

  Further, the shape of the screen was a rectangle having a width of 250 mm and a length of 150 mm.

  FIG. 6B is a graph in which the illuminance distribution in the horizontal direction and the vertical direction in the state where the cold cathode tube 103 is turned on is relatively plotted in the present embodiment. The horizontal axis of the graph represents the measurement position with the center of the screen being 0 in mm, and the vertical axis represents the measured relative luminance with the relative value with the center of the screen being 100. A solid line 107 indicates the distribution of relative luminance in the horizontal direction, and a broken line 108 indicates the distribution of relative luminance in the vertical direction. Looking at the graph, in this embodiment, the difference in luminance between the edge of the screen and the center of the screen is about four times.

Comparative example

  Next, a conventional liquid crystal display device 400 with a shutter function was produced as a comparative example, and the luminance distribution in the screen was measured.

  FIG. 6 is a diagram illustrating a comparative example.

  FIG. 5A is a cross-sectional view of the reflecting member 404 in this comparative example, and the unit of numerical values in the drawing is mm. Other conditions such as the reflective surface and the shape of the screen are the same as in the above-described embodiment.

  FIG. 5B is a graph in which the illuminance distribution in the horizontal direction and the vertical direction in the comparative example with the cold cathode tube 403 turned on is plotted in the same manner as in FIG. A solid line 407 indicates the distribution of relative luminance in the horizontal direction, and a broken line 408 indicates the distribution of relative luminance in the vertical direction. From this graph, it can be seen that in this comparative example, the luminance difference between the edge of the screen and the center of the screen is about 10 times.

  Thus, according to the present invention, it can be seen that more uniform illumination is obtained in the screen of the liquid crystal display device with a shutter function.

It is sectional drawing which shows the structure of the liquid crystal display device with a shutter function which concerns on 1st Embodiment. It is the figure which looked at the liquid crystal display with a shutter function concerning a 1st embodiment from the installation side. It is sectional drawing which shows the structure of the liquid crystal display device with a shutter function which concerns on 2nd Embodiment. It is sectional drawing which shows the structure of the liquid crystal display device with a shutter function which concerns on 3rd Embodiment. It is a figure which shows an Example. It is a figure which shows a comparative example. It is sectional drawing which shows the structure of the conventional liquid crystal display device with a shutter function.

Explanation of symbols

  100, 200, 300, 400 Liquid crystal display device with shutter function, 101, 201, 301, 401 Transmission type liquid crystal display device, 102, 202, 302, 402 Liquid crystal shutter, 103, 203, 303, 403 Cold cathode tube, 131 holder 104, 204, 304, 404 Reflecting member, 141, 241, 341, 441 Reflecting surface, 142, 242, 342, 442 Near reflecting surface, 143, 243, 343, 443 Outer reflecting surface, 144, 244, 344 444 Far reflection surface, 105, 205, 305, 405 Frame, 106, 206, 306, 406 Installation surface, 106, 206, 306, 406 Design surface, 107, 407 Relative luminance distribution in the horizontal direction, 108, 408 Vertical Distribution of relative luminance in the direction.

Claims (6)

A transmissive liquid crystal display device provided at a position separated from the installation surface;
A liquid crystal shutter provided on the installation surface side of the liquid crystal display device and capable of switching at least between a transparent state and an opaque state;
A light source provided on the installation surface side of the liquid crystal shutter and disposed along a peripheral edge of the liquid crystal shutter;
A reflecting member that surrounds the light source and has a reflecting surface that is open on the inside;
Have
The liquid crystal display device with a shutter function, wherein the reflection surface includes a surface inclined with respect to a surface on the installation surface side of the liquid crystal shutter in a cross section perpendicular to the surface on the installation surface side of the liquid crystal shutter.   2. The liquid crystal display with a shutter function according to claim 1, wherein the inclined surface is inclined so as to move away from the surface on the installation surface side of the liquid crystal shutter in a direction perpendicular to the inner side toward the outer side. apparatus.   2. The liquid crystal display with a shutter function according to claim 1, wherein the inclined surface is inclined so as to approach a direction perpendicular to the surface on the installation surface side of the liquid crystal shutter as it goes from the inside to the outside. apparatus. The reflective surface is
An outer reflective surface disposed outside the light source;
A near-side reflective surface that is disposed closer to the liquid crystal shutter than the light source and is inclined so as to be away from the surface on the installation surface side of the liquid crystal shutter in a direction perpendicular to the inner side to the outer side;
A far-side inclined surface that is disposed closer to the installation surface than the light source and is inclined so as to approach a direction perpendicular to the installation surface-side surface of the liquid crystal shutter, from the inside toward the outside;
The liquid crystal display device with a shutter function according to claim 1. The reflective surface is
An outer reflective surface disposed outside the light source;
A near-side reflecting surface that is disposed closer to the liquid crystal shutter than the light source and is substantially perpendicular to the outer reflecting surface;
A far-side reflection surface that is disposed closer to the installation surface than the light source and is substantially perpendicular to the outer reflection surface;
Have
The near-side reflection surface and the far-side reflection surface are inclined so as to move away from the surface on the installation surface side of the liquid crystal shutter in a direction perpendicular to the inner side to the outer side. LCD device with shutter function. The reflective surface is
An outer reflective surface disposed outside the light source;
A near-side reflecting surface that is disposed closer to the liquid crystal shutter than the light source and is substantially perpendicular to the outer reflecting surface;
A far-side reflection surface that is disposed closer to the installation surface than the light source and is substantially perpendicular to the outer reflection surface;
Have
The near-side reflection surface and the far-side reflection surface are inclined so as to approach a direction perpendicular to the surface on the installation surface side of the liquid crystal shutter from the inside toward the outside. LCD device with shutter function.

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