JP2006061261A - Liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display where the visibility of a rotation reel arranged behind a liquid crystal display panel is improved. <P>SOLUTION: The liquid crystal display is provided with: a transparent liquid crystal display panel 2 arranged on the front face side of the rotation reel 110 arranged rotatably and provided with an effective display part where a plurality of display pixels are arranged; and a surface light source apparatus 15 arranged between the liquid crystal display panel 2 and the rotation reel 110 to illuminate the liquid crystal display panel 2 from its rear side. The surface light source apparatus 15 is provided with: a light source part 20; and a light guide body 21 which has an opening part 21A opposing the rotation reel 110 and emits radiation light radiated from the light source part 20 toward the liquid crystal display panel 2. An edge 21E regulating the opening part 21A of the light guide body 21 has a nonlinear shape. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid crystal display device, and more particularly to a transmissive liquid crystal display panel and a liquid crystal display device including a surface light source device that illuminates the transmissive liquid crystal display panel.

  Liquid crystal display devices are utilized in various fields as display devices for OA equipment such as personal computers and information terminal equipment, taking advantage of features such as light weight, thinness, and low power consumption. In recent years, liquid crystal display devices are also used in gaming machines such as slot machines. A liquid crystal display panel mounted for use in a gaming machine is fitted, for example, over the entire display window of the casing (see, for example, Patent Document 1).

That is, a reel window is formed in the center of the liquid crystal display panel so that a lottery result based on the design of the rotating reel housed in the housing can be viewed from the outside. In such a gaming machine, when the display on the liquid crystal display panel is unnecessary, the driving of the liquid crystal display panel can be stopped so that the rotating reel on the back can be visually observed. Various images can be displayed around the rotating reel in a transparent state in a state where the rotating reel is visible.
JP 2000-308551 A

  The gaming machine having the above-described configuration includes a light emitting device. The emitted light from the light emitting device is reflected by a reflection plate inside the casing, illuminates the rotating reel housed inside the casing, and illuminates the liquid crystal display panel. Since the liquid crystal display panel displays an image by selectively transmitting illumination light from the back surface, even with such a configuration, there is no problem that visibility is deteriorated. However, since the rotating reel is observed from the front side (observer side) through the liquid crystal display panel, when illuminated from the back side, the front side is shaded, resulting in deterioration of visibility.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a liquid crystal display device capable of improving the visibility of a rotating reel disposed behind a liquid crystal display panel. is there.

A liquid crystal display device according to an aspect of the present invention
A transmissive liquid crystal display panel provided with an effective display portion arranged on the front side of a rotatable reel and arranged with a plurality of display pixels;
A surface light source device disposed between the liquid crystal display panel and the rotating reel and illuminating the liquid crystal display panel from the back side thereof, and a liquid crystal display device comprising:
The surface light source device includes a light source,
A light guide that has an opening facing the rotating reel and emits radiated light emitted from the light source toward the liquid crystal display panel;
The edge defining the opening of the light guide has a non-linear shape.

  According to the present invention, it is possible to provide a liquid crystal display device capable of improving the visibility of a rotating reel disposed behind the liquid crystal display panel.

  Hereinafter, a liquid crystal display device according to an embodiment of the present invention, particularly a liquid crystal display device that can be used for gaming machines will be described with reference to the drawings.

  As shown in FIG. 1, the liquid crystal display device 1 includes a transmissive liquid crystal display panel 2 having a substantially rectangular flat plate shape. The liquid crystal display panel 2 includes a pair of substrates, that is, an array substrate 3 and a counter substrate 4, and a liquid crystal layer 5 held between them as a light modulation layer. The liquid crystal display panel 2 includes a rectangular effective display unit 6 corresponding to a display area for displaying an image. The effective display unit 6 is composed of a plurality of display pixels PX arranged in a matrix.

  In the effective display section 6, the array substrate 3 extends along the column direction of the display pixels PX and a plurality of scanning lines Y (1, 2, 3,..., M) extending along the row direction of the display pixels PX. A plurality of existing signal lines X (1, 2, 3,..., N), connected to the switching elements 7 and switching elements 7 arranged for each display pixel PX in the vicinity of the intersection of the scanning lines Y and the signal lines X. The pixel electrode 8 and the like are provided.

  The switching element 7 is composed of a thin film transistor (TFT) or the like. The gate electrode 7G of the switching element 7 is electrically connected to the corresponding scanning line Y (or formed integrally with the scanning line). The drain electrode 7D of the switching element 7 is electrically connected to the corresponding signal line X (or formed integrally with the signal line). The source electrode 7S of the switching element 7 is electrically connected to the pixel electrode 8 of the corresponding display pixel PX.

  The counter substrate 4 includes a counter electrode 9 and the like common to all the display pixels PX in the effective display unit 6. The pixel electrode 8 and the counter electrode 9 are formed of a light-transmitting conductive material such as ITO (Indium Tin Oxide). The array substrate 3 and the counter substrate 4 are arranged with the pixel electrode 8 and the counter electrode 9 facing each other, and a gap is formed between them. The liquid crystal layer 5 is formed of a liquid crystal composition sealed in the gap between the array substrate 3 and the counter substrate 4.

  In the liquid crystal display panel 2, a pair of polarizing plates PL 1 and PL 2 whose polarization directions are set in accordance with the characteristics of the liquid crystal layer 5 are provided on the outer surface of the array substrate 3 and the outer surface of the counter substrate 4.

  In the color display type liquid crystal display device, the liquid crystal display panel 2 includes a plurality of types of display pixels, for example, a red pixel that displays red (R), a green pixel that displays green (G), and a blue that displays blue (B). Has pixels. That is, the red pixel includes a red color filter that transmits light having a red main wavelength. The green pixel includes a green color filter that transmits light having a green dominant wavelength. The blue pixel includes a blue color filter that transmits light having a blue main wavelength. These color filters are arranged on the main surface of the array substrate 3 or the counter substrate 4.

  The liquid crystal display panel 2 having such a configuration is disposed between a rectangular frame bezel cover 11 and a backlight 15 as a surface light source device. That is, the backlight 15 is integrated with the bezel cover 11 together with the liquid crystal display panel 2 with the surface thereof facing the back side (array substrate side) of the liquid crystal display panel 2. Illuminate from the side.

  A driver circuit 12 that supplies a drive signal to the liquid crystal display panel 2 is electrically connected to one side edge of the liquid crystal display panel 2 via a flexible printed wiring board 13. The driver circuit 12 is arranged on the back side of the backlight 15 by curving the printed wiring board 13.

  As illustrated in FIGS. 1 to 3, the backlight 15 includes a light source unit 20, a light guide 21, and the like. The light source unit 20 includes a cold cathode tube 22 and a lamp reflector 23 as a light source. That is, the cold cathode tube 22 is an elongated cylindrical tubular light source extending in the longitudinal direction of the rectangular light guide 21. The lamp reflector 23 reflects the radiated light emitted from the cold cathode tube 22 toward the light guide 21, and is disposed so as to surround the cold cathode tube 22.

  The light guide 21 is formed of a resin material such as an acrylic resin or a polycarbonate resin having light transmittance. Here, the light guide 21 is formed in a substantially rectangular shape, and is formed in a substantially uniform thickness throughout. The light guide 21 includes a first main surface 21b facing the liquid crystal display panel 2, a second main surface 21d facing the first main surface 21b, and the first main surface 21b and the second main surface 21d. The first side surface 21a and the second side surface 21c are connected to each other.

  In this embodiment, the light source unit 20 is disposed along a pair of long sides 21 </ b> L of the light guide 21. That is, the cold cathode tube 22 is disposed so as to face the first side surface 21 a and the second side surface 21 c along the long side 21 </ b> L of the light guide 21 substantially in parallel. That is, the first side surface 21a and the second side surface 21c of the light guide correspond to a light incident surface on which the emitted light from the cold cathode tube 22 is incident.

  The light guide 21 having such a configuration propagates linear radiation from the cold cathode tube 22 incident through the first side surface 21a and the second side surface 21c, and the first main surface 21b and the second main surface. 21d can be emitted. In other words, the first main surface 21 b and the second main surface 21 d of the light guide 21 correspond to an emission surface that emits light incident on the light guide 21.

  The substantially rectangular optical sheet 24 is disposed so as to cover the first main surface 21 b of the light guide 21. The optical sheet 24 gives a predetermined optical characteristic to the outgoing light emitted from the first main surface 21b of the light guide 21. For example, the optical sheet 24 collects the outgoing light from the first main surface 21b. And a diffusion sheet for diffusing the light emitted from the first main surface 21b.

The substantially rectangular optical sheet 25 is arranged so as to cover the second main surface 21 d of the light guide 21. The optical sheet 25 is a reflection sheet that reflects the emitted light emitted from the second main surface 21 d of the light guide 21 toward the light guide 21 again.
The light source unit 20, the light guide 21, and the optical sheets 24 and 25 are accommodated in a substantially rectangular frame 30.

  The liquid crystal display device configured as described above operates as follows. That is, electric energy is supplied to the cold cathode tubes 22 of the pair of light source units 20 to cause the cold cathode tubes 22 to emit light. The linear radiation emitted from the cold cathode tubes 22 is reflected by the inner surface of the lamp reflector 23 covering the cold cathode tubes 22, and directed toward the first side surface 21a and the second side surface 21c of the light guide 21, respectively. Is derived. Incident light that has entered from the first side surface 21 a and the second side surface 21 c of the light guide 21 propagates through the light guide 21 toward the first main surface 21 b and the second main surface 21 d of the light guide 21. Refracted or reflected. The emitted light emitted from the second main surface 21 d of the light guide 21 is reflected again toward the inside of the light guide 21 by the optical sheet 25.

  The emitted light emitted from the first main surface 21b of the light guide 21 is given predetermined optical characteristics such as being appropriately condensed or moderately diffused when passing through the optical sheet 24. Thereby, the brightness | luminance of the emitted light radiate | emitted from the 1st main surface 21b of the light guide 21 is improved, and it is made uniform.

  Illumination light from the backlight 15, that is, light that has passed through the optical sheet 24 is led out to the back side of the liquid crystal display panel 2. The illumination light derived to the liquid crystal display panel 2 selectively transmits through the effective display unit 6 of the liquid crystal display panel 2. Thereby, an image is displayed on the effective display section 6 of the liquid crystal display panel 2.

  Next, the liquid crystal display device 1 used for a gaming machine such as a slot machine will be described. That is, as shown in FIGS. 1 and 3, the gaming machine includes a rotating reel 110 that is rotatably arranged inside the housing 100. The rotary reel 110 includes a plurality of, for example, three cylindrical reel bodies 111 that can rotate around a rotation axis O, and a belt-like reel tape 112 that is attached to the cylindrical surface of the reel body 111. . The reel tape 112 has a plurality of patterns arranged at equal intervals.

  The liquid crystal display device 1 is disposed on the front side (that is, the observer side) of the rotating reel 110 inside the housing 100. That is, the liquid crystal display panel 2 is disposed on the front side of the rotating reel 110, and the backlight 15 is disposed between the liquid crystal display panel 2 and the rotating reel 110. The housing 100 includes a window portion 102 that allows an image displayed on the liquid crystal display device 1 to be viewed, and the window portion 102 includes a protective plate 103 having a light transmission property such as a glass plate.

  The backlight 15 mounted on such a liquid crystal display device 1 has an opening 15 </ b> A corresponding to the position where the rotary reel 110 is disposed at the approximate center thereof. That is, the light guide 21 has an opening 21 </ b> A that faces the rotating reel 110. Similarly, the optical sheet 24 has an opening 24A at a position corresponding to the opening 21A. Further, the optical sheet 25 similarly has an opening 25A at a position corresponding to the opening 21A. Such an opening 15 </ b> A of the backlight 15 has a substantially rectangular shape, and allows a predetermined number of patterns on the rotary reel 110 located behind the backlight 15 to be viewed.

  Thereby, the weight of the light guide 21 is reduced, and the liquid crystal display device 1 can be reduced in weight. Further, since the rotary reel 110 can be viewed without using the backlight 15, the visibility of the rotary reel 110 can be improved.

  By the way, in the liquid crystal display panel 2 described above, it is possible to display an image on the entire effective display unit 6 in the first display mode, and the opening of the backlight 15 in the effective display unit 6 in the second display mode. It is possible to form a light transmission state without displaying an image in an area located on the part 15A and display an image in another area. In the second display mode, the design of the rotating reel 110 can be viewed through the liquid crystal display panel 2.

  In particular, in the first display mode, when an image is displayed on the entire effective display section 6 of the liquid crystal display panel 2, there is a possibility that the brightness is different between the area located on the opening 15A and the other areas. That is, in the effective display unit 6, the luminance of the region located on the light guide 21 is relatively high, and the luminance of the region located on the opening 15A is likely to be relatively low. For this reason, due to these luminance differences, the edge 21E that defines the opening 21A of the light guide 21 is easily visually recognized. In particular, the straight edge 21E is easily visually recognized.

  Therefore, the edge 21E of the opening 21A is formed in a non-linear shape. In this embodiment, the opening 21A has a substantially rectangular shape, and the four edges 21E each have a non-linear shape. As described above, the edge 21E has a non-linear shape, so that the display pixel PX located on the light guide 21 and the display located on the opening 21A in the region located on the opening 15A in the effective display portion 6 are displayed. Pixels are scattered in the same row and the same column.

  For this reason, when the image is displayed in the first display mode in the effective display unit 6, the luminance in the area near the edge 21E of the opening 21A is averaged, and the edge 21E is hardly visible. Thereby, it is possible to improve the display quality of the image.

  Here, as shown in FIG. 4, the non-linear shape is a convex portion CV protruding inward of the opening 21 </ b> A with respect to a schematic rectangular frame 21 </ b> F that defines the opening 21 </ b> A of the light guide 21. This corresponds to a corrugated shape having a recess CC recessed outward of the opening 21A. Various patterns can be applied as the wave shape.

  That is, as shown in FIG. 4, the edge 21E of the opening 21A may have a rectangular wave shape. In the edge 21E having such a shape, both the convex portion CV and the concave portion CC are formed by a substantially rectangular pattern.

  Further, as shown in FIG. 5, the edge 21E of the opening 21A may have a sawtooth wave shape. In the edge 21E having such a shape, both the convex portion CV and the concave portion CC are formed in a substantially triangular pattern. Such a corrugated shape hardly interferes with the layout of the display pixels PX arranged in a matrix in the effective display portion 6 when the liquid crystal display panel 2 and the backlight 15 are combined, and the visibility of the edge 21E is further improved. Further reduction is possible.

  Furthermore, as shown in FIG. 6, the edge 21E of the opening 21A may have a curved corrugated shape. In the edge 21E having such a shape, both the convex portion CV and the concave portion CC are formed by a substantially arc-shaped pattern. That is, the end surface 21S of the opening 21A along the curved edge 21E is a curved surface. Such a corrugated shape hardly interferes with the layout of the display pixels PX arranged in a matrix in the effective display portion 6 when the liquid crystal display panel 2 and the backlight 15 are combined, and the visibility of the edge 21E is further improved. Further reduction is possible.

  In the example shown in FIGS. 4 to 6, the case where the corrugated shape has the convex portions CV and the concave portions CC regularly arranged at the predetermined pitch P has been described. However, the predetermined pitch is the pitch of the display pixel PX. It is desirable that the value is larger, and various values are set according to the size of the effective display portion 6, the size of the opening 21A, the display luminance, and the like.

  Further, the corrugated shape may have convex portions CV and concave portions CC arranged at an irregular pitch. Further, the corrugated shape may include a plurality of convex portions CV projecting from the rectangular frame 21F, and may include a plurality of concave portions CC having different dimensions recessed from the rectangular frame 21F. good. When these waveform shapes are employed, the luminance in the region near the edge 21E of the opening 21A is further averaged in the effective display portion, and the edge 21E is less likely to be visually recognized.

  As described above, according to the liquid crystal display device usable for the gaming machine according to this embodiment, the opening is formed in the light guide of the backlight corresponding to the position where the rotating reel is provided. . Thereby, the weight of the light guide is reduced, and the liquid crystal display device 1 can be reduced in weight. Further, since the rotating reel can be viewed without going through the backlight, the visibility of the rotating reel can be improved.

  In addition, since the edge that defines the opening of the light guide has a non-linear shape, the edge is difficult to be visually recognized. For this reason, the display quality of the image can be improved.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the components without departing from the gist of the invention in the stage of implementation. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

FIG. 1 is an exploded perspective view schematically showing the structure of a liquid crystal display device according to an embodiment of the present invention. FIG. 2 is an exploded perspective view schematically showing a structure of a backlight mounted on the liquid crystal display device shown in FIG. FIG. 3 is a cross-sectional view schematically showing the structure of a liquid crystal display device used in a gaming machine. FIG. 4 is a diagram for explaining a first shape example of the opening in the light guide of the backlight shown in FIG. FIG. 5 is a diagram for explaining a second shape example of the opening in the light guide of the backlight shown in FIG. FIG. 6 is a view for explaining a third shape example of the opening in the light guide of the backlight shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display device, 2 ... Liquid crystal display panel, 15 ... Backlight (surface light source device), 15A ... Opening part, 20 ... Light source part, 21 ... Light guide, 21A ... Opening part, 21E ... Edge, 21F ... Rectangular Frame, 21S ... end face, 21a ... first side, 21b ... first main surface, 21c ... second side, 21d ... second side, 22 ... cold cathode tube (light source), 23 ... lamp reflector, 24 ... optical sheet, 25 ... Optical sheet, 30 ... Frame, 100 ... Housing, 110 ... Rotary reel, 111 ... Reel body, 112 ... Reel tape, CV ... Convex part, CC ... Concave part

Claims (7)

A transmissive liquid crystal display panel provided with an effective display portion arranged on the front side of a rotatable reel and arranged with a plurality of display pixels;
A surface light source device disposed between the liquid crystal display panel and the rotating reel and illuminating the liquid crystal display panel from the back side thereof, and a liquid crystal display device comprising:
The surface light source device includes a light source,
A light guide that has an opening facing the rotating reel and emits radiated light emitted from the light source toward the liquid crystal display panel;
A liquid crystal display device, wherein an edge defining an opening of the light guide has a non-linear shape.   The liquid crystal display device according to claim 1, wherein the opening has a substantially rectangular shape, and each of the four edges has a non-linear shape.   The liquid crystal display device according to claim 1, wherein the edge has a corrugated shape having a convex portion protruding inward of the opening and a concave portion recessed outward of the opening.   The liquid crystal display device according to claim 3, wherein the edge has a rectangular corrugated shape.   The liquid crystal display device according to claim 3, wherein the edge has a sawtooth wave shape.   The liquid crystal display device according to claim 3, wherein the edge has a curved corrugated shape.   The said surface light source device is provided with the optical sheet which provides a predetermined | prescribed optical characteristic to the emitted light radiate | emitted from the said light guide between the said light guide and the said liquid crystal display panel. A liquid crystal display device according to 1.

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