JP2002365628A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To deepen the depth of the fixed display when it is visually confirmed and to diversify display states and display colors, in a liquid crystal display device by which the fixed display can be executed while being three- dimensionally superposed on the display by a liquid crystal display panel. SOLUTION: A light guide plate 13 for fixed display having a recessed and/or projecting display 13E formed on the surface of a light guide plate 12 side for illuminating the liquid crystal display panel is provided between a transmission type liquid crystal display panel 16 and the light guide plate 12 for illuminating the liquid crystal display panel. Separate light sources 14 and 15 for respectively emitting light into the light guide plate 12 for illuminating the liquid crystal display panel and the light guide plate 13 for fixed display are provided corresponding to the respective light guide plates 12 and 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal display (Liquid Crystal Display) using a transmission type liquid crystal display panel and a light guide plate.
Display).

[0002]

2. Description of the Related Art As a liquid crystal display device using a transmission type liquid crystal display panel and a light guide plate, display by a liquid crystal display panel,
Some of them are capable of displaying both a fixed display and a concave or convex portion formed on the surface of the light guide plate.
This is introduced in Japanese Patent Application Laid-Open No. 2000-29909. FIG. 7 is a cross-sectional view schematically showing one conventional example of the liquid crystal display device described in the publication.

In FIG. 1, reference numeral 1 denotes a substrate on which a light guide plate 2 is mounted, and a light source 3 is opposed to one side surface of the light guide plate 2. The light guide plate 2 is made of a transparent material such as acrylic or polycarbonate. The surface (upper surface) of the light guide plate 2 is a light emitting surface 2A that emits light by diffusing light, and the rear surface (lower surface) is a light reflecting surface 2B. . On the light emitting surface 2A side of the light guide plate 2, a transmissive (illuminated positive type in which the back is transparent and the characters and the like are black) is provided.

In this type of liquid crystal display device, when light emitted from the light source 3 is incident on the side surface of the light guide plate 2, the incident light is reflected on the reflection surface 2B, diffused on the light emission surface 2A, and emits light over the entire surface. . The entire surface of the liquid crystal display panel 4 is illuminated by the light emitting surface 2A, and, for example, a display with a light source color on the back and black characters and the like can be performed. In such a liquid crystal display device,
Since the light-emitting surface 2A of the light guide plate 2 is located directly below the liquid crystal display panel 4, the characters and the like displayed on the liquid crystal display panel 4 are displayed with no sense of depth (ie, two-dimensional display). Would.

Further, a concave light-condensing pattern is formed on the surface of the light guide plate 2 on the light-emitting surface 2A side, and a figure or the like is fixedly displayed on the display panel 4 by the light-condensing pattern. However, in such a display method, since the concave light-condensing pattern is located immediately below the liquid crystal display panel 4, the display of this light-condensing pattern overlaps the display of the liquid crystal display panel 4, and there is no depth. Poor visibility and poor appearance.

In order to solve such a drawback, in the technique of the above-mentioned document, the light guide plate 2 has a two-layer structure, and a concave condensing pattern is formed on the back surface of the first light guide plate on the liquid crystal display panel 4 side. The light from the light source 3 is incident on the side surface of the light guide plate 2 having the two-layer structure, and the display from the liquid crystal display panel 4 to the display by the light guide plate 2 is given a sense of depth to provide a stereoscopic display. We are trying to improve the appearance.

[0007]

By the way, the above-mentioned liquid crystal display device using the light guide plate 2 having the two-layer structure has the following problems.
Since the fixed display of the condensing pattern of the light guide plate 2 and the illumination of the liquid crystal display panel 4 are performed using the three light sources 3, there is a problem that the display of the condensing pattern cannot be switched on and off. In addition, since the display by the liquid crystal display panel 4 and the fixed display by the light guide plate 2 are performed by using one light source 3, these two displays have the same color, so that multicolor display cannot be performed. For this reason, there is a problem that the display mode becomes a single display mode and lacks novelty.

The present invention has been made to solve such problems, and has a relatively simple structure, the number of display modes can be increased by multicoloring, etc. It is an object of the present invention to provide a new liquid crystal display device capable of performing a selection display from a display.

[0009]

According to a first aspect of the present invention, there is provided a liquid crystal display device comprising: a transparent liquid crystal display panel; and a light guide plate for illuminating the liquid crystal display panel. And / or a light guide plate for fixed display on which a display by a convex is formed, and a light guide plate for illuminating a liquid crystal display panel and a separate light source incident on the light guide plate for the fixed display light guide plate are provided. And

Therefore, according to the liquid crystal display device of the first aspect, the light guide plate for illuminating the liquid crystal display panel and the separate light sources incident on the light guide plate for the fixed display are provided. It is possible to independently control lighting and extinguishing, and a state where only display is performed by the liquid crystal display panel, a state where only fixed display is performed, and both display and fixed display by the liquid crystal display panel are performed It is possible to arbitrarily create three states.

[0011] By changing the color of the light from the light source, multicolor can be achieved. Further, concave and / or convex portions for performing a fixed display are formed on the surface of the light guide plate for a fixed display on the side opposite to the liquid crystal display panel, so that the fixed display guide is provided between the display by the display and the display by the liquid crystal display panel. Since there is an interval having a size substantially equal to the thickness of the light plate, when viewing the display from the front, a sense of depth is generated in the fixed display, and a sense of floating is generated in the display by the liquid crystal display panel. Therefore, three-dimensional display becomes possible.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention basically provides a fixed display light guide plate between a transmission type liquid crystal display panel and a liquid crystal display panel light guide plate, and provides a liquid crystal display panel light guide. A light plate and a separate light source incident on the light guide plate are provided corresponding to each of the fixed display light guide plate, and the fixed display by the fixed display light guide plate is a surface on the liquid crystal display panel illumination light guide plate side (back surface). This is done by the recesses and / or protrusions formed in the substrate. In the present invention, the fixed display by the fixed display light guide plate includes all of the case of selectively displaying, in addition to characters, figures, patterns, pictures, and the like. Therefore, it includes those in which only a predetermined area emits light, and the area is substantially illuminated.

[0013] A plurality of light sources for projecting light on the side surfaces of the fixed display light guide plate are provided, and the fixed display light guide plate is provided with a light source corresponding to each of the fixed display light sources. There may be an embodiment in which a fixed display portion composed of a concave portion that reflects only the light on the liquid crystal display panel side and transmits the other light is provided. For example, if the cross-sectional shape of the concave portion is a right triangle, the vertical side constituting the concave portion passes light traveling substantially parallel to the front and back surfaces in the light guide plate, but the hypotenuse reflects light in a specific direction. It is preferable to provide a display composed of concave portions having different directions, and to arrange the light source so that light reflected on the oblique side of the concave portion of the display corresponding to the light source can be radiated into the light guide plate. Then, in this case, if the colors of a plurality of light sources that make light incident on one fixed display light guide plate are different from each other, the teaching of the liquid crystal display device can be made multi-colored. In addition, if each of the light sources can be individually controlled to be turned on / off independently, expression can be diversified. As described above, the present invention can have various embodiments, and can have various variations.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. 1A to 1C show a schematic configuration of a first embodiment of the liquid crystal display device of the present invention, wherein FIG. 1A is a plan view, FIG. 1B is a side view, and FIG. It is an exploded perspective view.
2 (A) to 2 (C) are diagrams showing a lighting state of the light source in FIG. 1, (A) is a diagram when the liquid crystal display panel is illuminated, and (B)
FIG. 3 is a view when the illumination area is illuminated, and FIG.

This liquid crystal display device has a substrate 11, on which a light guide plate 12 for illuminating a liquid crystal display panel is mounted, and on this light guide plate 12, a light guide plate 13 for fixed display is mounted. Have been. On the substrate 11, for example, on the left side of the light guide plate 12, for example, two liquid crystal display panel illumination light sources 14-1 and 14-that can be turned on and off.
2 are installed. The light sources 14-1 and 14-2 for illuminating the liquid crystal display panel are configured by, for example, light emitting diodes (hereinafter, referred to as “LEDs”) that emit blue light. Further, on the substrate 11, for example, two fixed display light sources 15-1 and 15-2 that can be turned on and off are attached to, for example, the right side of the light guide plate 12. The fixing display light sources 15-1 and 15-2 are configured by, for example, LEDs that emit red light. Light guide plate 12,
13 is a light transmittance of 8 such as acrylic or polycarbonate.
It is formed by molding or the like using a transparent material of about 0 to 95%.

On the fixed display light guide plate 13, a liquid crystal display panel 16 of a transmission type (for example, an illuminated positive type) is provided. As the liquid crystal display panel 16, a TN type (however,
N is a nematic liquid crystal), IPS type (however, S is a smectic liquid crystal), GH type, ECB type, STN type, PC
Shapes, polymer dispersion types, ferroelectric types and other structures can be employed.

A light emitting surface 12A for diffusing light is formed on the front side of the light guide plate 12 for illuminating the liquid crystal display panel, and a reflective surface 12B is formed on the back side. The light emitting surface 12A is formed in a rough surface by etching, blasting, or the like. The light guide plate 12 includes a light source 14
-1 and 14-2 are incident on the side surface, and the incident light is totally reflected by the reflecting surface 12B while the light emitting surface 12
B diffuses and transmits light to illuminate the entire surface of the liquid crystal display panel 16.

The light guide plate 13 for fixed display provided on the light guide plate 12 includes a flat display portion 13A and a display portion 13A.
For example, the incident part 13 whose right side is bent in a substantially right-angle direction.
B, and the light source 15-1,
15-2 is incident. Display unit 13
On the front side of A, a mirror-finished reflective surface 13 for reflecting light
C is formed, and a bent portion between the display unit 13A and the incident unit 13B is cut to, for example, about 45 ° to form a mirror-finished reflection surface 13D. An illumination area 13E is formed at a predetermined position on the back side of the display unit 13A. In the illumination area 13E, an uneven surface (for example, a rough surface with very fine unevenness) is formed by etching, blasting, or the like. In a region other than the illumination area 13E on the back surface side of the display unit 13A, a mirror-finished reflection surface is formed.

Light from the light sources 15-1 and 15-2 enters from an incident portion 13B of the light guide plate 13, and after this incident light is totally reflected by a reflection surface 13D, a reflection surface on the front side of the display portion 13A. 13C and the illumination area (also a kind of fixed display in the present invention) that is totally reflected between the reflection surface 13C and the reflection surface on the back side 13
At E, the light is reflected in the direction of the liquid crystal display panel 16 and only the illumination area 13E emits light. That is, the illumination area 13E emits light when the light from the light sources 15-1 and 15-2 enters, and transmits the light from the light guide plate 12 toward the liquid crystal display panel 16 when the light does not enter. It has a function to make it work.

FIGS. 3A to 3C are for explaining the operation of the liquid crystal display device shown in FIGS. 1 and 2. FIG.
Is a plan view of the liquid crystal display device, (B) is a side view of the liquid crystal display device, (C) is an enlarged view of an illumination area portion of the light guide plate,
4A and 4B are plan views showing a display state of the liquid crystal display panel of FIGS. 1 and 2, wherein FIG. 4A shows a state when the fixed display light source is in an off state, and FIG. 5 shows a state when the fixed display light source is on, and FIG. 5 is a plan view showing a display state of the liquid crystal display panel when the fixed display light source shown in FIG. 1 is off.

Hereinafter, the operation of the liquid crystal display device shown in FIGS. 1 and 2 will be described with reference to FIGS. For example, the blue light sources 14-1 and 14-2 for illuminating the liquid crystal display panel are turned on, and the red light sources 15-1 and 15-1 for illuminating the illumination area.
5-2 is turned off, and the liquid crystal display panel 16 displays the display information (for example, the characters “STEREO” or “time”).
Is displayed.

As shown in FIG. 2A, the blue light emitted from the light sources 14-1 and 14-2 in the ON state enters from the left side of the light guide plate 12. This incident light is transmitted through the light guide plate 1
The light is totally reflected by the second reflecting surface 12B, diffused by the light emitting surface 12A, and the entire surface of the light emitting surface 12A emits light. Red light source 1
Since 5-1 and 15-2 are in the off state, the light guide plate 13 is in a state of transmitting light from the light guide plate 12 including the illumination area 13E. For this reason, the light emitting surface 12 of the light guide plate 12
The blue light emitted in the entire area at A passes through the light guide plate 13 and illuminates the liquid crystal display panel 16.

As a result, as shown in FIG. 4A, black characters (for example, “STER”) are displayed on the liquid crystal display panel 16.
EO ”) is clearly displayed. Here, since the light emitting surface 12A of the light guide plate 12 illuminates the liquid crystal display panel 16 through the distance T by the thickness of the light guide plate 13 thereon, as shown in FIG. Black characters (for example, “time”) can be displayed.

Next, the red light sources 15-1 and 15-2 are turned on while the blue light sources 14-1 and 14-2 are turned on. As shown in FIG. 2B, the light source 15-
When the light sources 15-1 and 15-2 are turned on, the light sources 15-1 and 15-1
Red light is emitted upward from 15-2 and is incident on the incident portion 13 </ b> B of the light guide plate 13. This incident light is transmitted to the light guide plate 13.
Totally reflected by the reflection surface 13D, and advances at a shallow angle with respect to the upper and lower surfaces of the display unit 13A. The display area 13A includes an illumination area 1
Since the reflection surface 13C is formed on the front side and the back side except for 3E, the red light repeats total internal reflection except for the illumination area 13E.

Since the illumination area 13E has very fine irregularities, it is reflected toward the liquid crystal display panel 16 and the illumination area 13E emits red light. As a result, as shown in FIG.
Are illuminated in red around the characters (for example, “STEREO”) displayed in. Therefore, for example, when the stereo switch is turned on, the red light sources 15-1, 1
If 5-2 is also turned on, the area around the display characters (for example, “STEREO”) on the liquid crystal display panel 16 turns red, and it can be visually observed that the stereo switch has been turned on.

As described above, the first embodiment has the following effects (1) to (3). (1) Liquid crystal display panel 16 and light source 14 for illuminating it
-1, 14-2 and the light guide plate 12, the light source 1 for fixed display
By simply adding 5-1 and 15-2 and the light guide plate 13, the double display can be performed with a simple structure and relatively inexpensively. In particular, since the light sources 15-1 and 15-2 for fixed display and the light sources 14-1 and 14-2 for liquid crystal display panel display are independent, each display can be turned on and off. The display by the display panel 16 and the display by the light guide plate 13 can be separately colored.

(2) The display from the liquid crystal display panel 16 to the display on the light guide plate 13 has a sense of depth. In particular, the display on the liquid crystal display panel 16 is a three-dimensional display with a floating feeling floating in space. It becomes possible, and a novel display design can be achieved. (3) Illumination area 1 formed on the back side of light guide plate 13
3E has a configuration in which, for example, the whole is made to emit red light. Instead of this, for example, a character such as a character is displayed by forming a concave character or the like by engraving and performing blast processing or the like on the concave surface portion. Alternatively, a figure or the like may be displayed in an uneven shape.

FIGS. 6A to 6C show a schematic structure of a light guide plate for fixed display according to a second embodiment of the liquid crystal display device of the present invention. FIG. 6A is a side view of the light guide plate. (B), (C)
FIG. 4 is an enlarged view of another example of the illumination area portion. The fixed display light guide plate 23 has an incident portion 23B-1 whose right side is bent in a substantially right angle direction, and also has an incident portion 23B-2 which is bent in a substantially right direction on the left side. . As shown in FIG. 1A, the right incident part 23B-
1, two second light sources 15-1, 15 such as LEDs,
15-2 is arranged, and the left incident part 23B-2
Below, two fixed display light sources 15-3, such as LEDs,
15-4 (however, 15-4 does not appear in the drawing). These two light sources 15-3 and 15-4 are attached so as to avoid the liquid crystal display panel illumination light sources 14-1 and 14-2.

Illumination areas 23E-1 and 23E-2 are formed at two places on the back side of the light guide plate 23, and the other places on the back side are mirror-finished reflection surfaces. FIG.
As shown in (B) or (C), left side illumination (display)
The area 23E-1 is formed with a large number of substantially right-angled triangular recesses formed by a surface perpendicular to a slope that reflects light from the left side upward, and light from the right side is provided in the right illumination area 23E-2. A large number of recesses having a substantially right-angled triangular cross section formed by a surface perpendicular to the inclined surface that reflects light upward.

Accordingly, when the left light source 15-3 (15-4) is turned on, the left illumination area 23E-1 emits the color of the light source upward (toward the liquid crystal display panel) and the right light source 15-1. The effect of (15-2) is hardly affected. The right illumination area 23E-2 is provided on the right light source 15-1.
When (15-2) is turned on, the color of the light source is emitted upward (toward the liquid crystal display panel), and the left light source 15-3 (15-
The effect of 4) is hardly affected. Therefore, the right light source 1
5-1 (15-2) and the left light source 15-3 (15-4)
, One or both of the right illumination area 23E-2 and the left illumination area 23E-1 can be illuminated arbitrarily.

As described above, in the second embodiment, the light sources 15-1 and 15-2 and the light sources 15-3 and 15-3 having different emission colors are used.
15-4, and 2 on the light emitting plate 23 for fixed display.
Since the two illumination areas 23E-1 and 23E-2 are formed, two figures, characters, and the like can be displayed in different colors, whereby the display design can be diversified.

The present invention is not limited to the above embodiment,
Various modifications are possible. For example, there are the following modifications (1) to (4). (1) Light sources 15-1, 15-2, 15- for fixed display
By changing the emission colors of 3, 15-4, or by increasing the number of these light sources to increase the emission colors, the illumination area 13E, 2
It is possible to increase the display colors of 3E-1 and 23E-2.

(2) Light guide plates 13 and 23 for fixed display
Has a flat plate-like structure without the incident portions 13B, 23B-1, 23B-2, and the light sources 15-1, 1
5-2, 15-3, and 15-4 may be provided. Also, the illumination areas 13E, 23E-1, 23E-2
May be formed at an arbitrary position on the back surface of the light guide plates 13 and 23 or may be formed by an arbitrary number.

(3) Light sources 14-1, 14-2, 15-
As 1,15-2,15-3,15-4, other light sources such as lamps may be used in addition to LEDs. (4) Illumination areas 13E, 23E-1, 23E-2
May have other irregularities than those shown.

[0035]

According to the liquid crystal display device of the first aspect of the present invention, the light guide plate for illuminating the liquid crystal display panel and the separate light source incident on the light guide plate for the fixed display are provided. It is possible to control the lighting and extinguishing independently, a state where only the display by the liquid crystal display panel is performed,
It is possible to arbitrarily create three states, that is, a state where only fixed display is performed and a state where both display and fixed display are performed by the liquid crystal display panel.

By changing the color of the light from the light source, multicoloring can be achieved. Further, concave and / or convex portions for performing a fixed display are formed on the surface of the light guide plate for a fixed display on the side opposite to the liquid crystal display panel, so that the fixed display guide is provided between the display by the display and the display by the liquid crystal display panel. Since there is an interval having a size substantially equal to the thickness of the light plate, when viewing the display from the front, a sense of depth is generated in the fixed display, and a sense of floating is generated in the display by the liquid crystal display panel. Therefore, three-dimensional display becomes possible.

According to the liquid crystal display device of the present invention, a plurality of light sources for fixed display are provided, and only light from the light source corresponding to the light source for fixed display is provided on the liquid crystal display panel side. Since a fixed display section composed of a concave portion that reflects and transmits other light is provided so that each of the fixed display light sources can be individually turned on / off, the display state of each of the plurality of fixed display sections can be set to the display state or not. It is possible to control whether to make the display state.

According to the liquid crystal display device of the third aspect, since the colors of the fixed display light sources are different, it is possible to achieve multi-color display.

[Brief description of the drawings]

FIGS. 1A to 1C are schematic configuration diagrams of a liquid crystal display device according to a first embodiment of the present invention, FIG.
(B) is a side view, and (C) is a schematic exploded perspective view.

2 (A) to 2 (C) are diagrams showing a lighting state of the light source in FIG. 1; FIG. 2 (A) is a diagram when a liquid crystal display panel is illuminated;
(B) is a figure at the time of illumination of an illumination area, (C) is a partial enlarged view of a light guide plate.

3 (A) to 3 (C) are explanatory diagrams of the operation of the liquid crystal display device of FIGS. 1 and 3; FIG. 3 (A) is a plan view of the liquid crystal display device;
(B) is a side view of the liquid crystal display device, and (C) is an enlarged view of an illumination area portion of the light guide plate.

4A and 4B are diagrams showing a display state of the liquid crystal display panel of FIGS. 1 and 3, wherein FIG. 4A is a diagram when an illumination area is in an off state, and FIG. FIG. 5 is a diagram when is turned on.

FIG. 5 is a diagram showing a display state of the liquid crystal display panel when the illumination area of FIG. 1 is in an off state.

FIGS. 6A to 6C are other schematic configuration diagrams of a fixed display light guide plate according to a second embodiment of the present invention, wherein FIG. 6A is a side view of the light guide plate, and FIG. (C) is an enlarged view of an illumination area portion.

FIG. 7 is a schematic sectional view showing a configuration example of a conventional liquid crystal display device.

[Description of Signs] 12 ... Light guide plate for illuminating liquid crystal display panel, 13, 23
..Light guide plate for fixed display, 13E, 23E ... lighting (display) area, 14 ... light source for liquid crystal display panel lighting, 15-1, 15-2, 15-3, 15-4 ...
Second light source, 16: liquid crystal display panel.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09F 13/18 G09F 13/18 NF term (Reference) 2H038 AA55 BA06 2H091 FA14Z FA23Z FA31Z FA45Z FB03 FC17 FD13 GA01 HA06 LA15 LA16 5C094 AA48 AA51 AA60 BA43 CA24 CA30 DA02 DA03 DA05 ED01 FA02 5C096 AA11 AA14 AA22 BA01 BA02 BB17 BC02 BC04 BC11 BC12 BC15 BC16 CA06 CA15 CA22 CA32 CA35 CC06 CD02 CD05 CD10 CD16 CD23 CD28 DC02 DC35 DC01 DC02 BB15 CC11 EE27 FF03 FF08 GG23 GG26

Claims (3)

[Claims] 1. A transmissive liquid crystal display panel, and a liquid crystal display panel illuminating the liquid crystal display panel, which is disposed on the back side of the liquid crystal display panel and serves as a surface light source for illuminating the liquid crystal display panel by multiply reflecting incident light from a side surface. A light guide plate; a liquid crystal display panel illumination light source for supplying illumination light to the liquid crystal display panel illumination light guide plate; and a liquid crystal display disposed between the liquid crystal display panel and the liquid crystal display panel illumination light guide plate. A fixed display light guide plate having a fixed display portion with a concave portion and / or a convex portion on the surface on the side of the panel illumination light guide plate, wherein incident light from a side surface is reflected by the fixed display portion to perform fixed display; A liquid crystal display device, comprising: a display panel light source for supplying display light to the display light guide plate. 2. A light source for a fixed display, comprising a plurality of light sources for a fixed display, wherein the light guide plate for a fixed display has a recess corresponding to each of the fixed display light sources and reflecting only light from the light source toward the liquid crystal display panel. 2. The liquid crystal display device according to claim 1, further comprising a fixed display unit, wherein each of the fixed display light sources is individually turned on / off. 3. The liquid crystal display device according to claim 2, wherein the plurality of fixed display light sources have different colors.