JP2005166514A - Sheet-like light source unit for color display device and liquid crystal color display structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet-like light source unit for a color display device and a liquid crystal color display structure capable of providing uniform color display even in the case of directly and closely watching the display device. <P>SOLUTION: The sheet-like light source unit 1 for a color display device mainly comprises a plurality of single color light sources 3A, 3B, etc emitting lights of different colors, a reflecting plate 4 for reflecting the lights from the light sources 3A and the like to form reflected lights, and a light diffusion plate 2 for receiving the reflected lights and transmitting them. As the light sources 3A and the like, a total of three light sources emitting three primary colors of red (R), green (G) and blue (B), respectively, are generally used. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light source unit for a color display device and a liquid crystal color display structure, and in particular, a backlight for irradiating light from the back side of a display device such as a color liquid crystal panel or an electric signboard, or a color for irradiating light from the front side. The present invention relates to a planar light source unit for a color display device and a liquid crystal color display structure suitable for a light emitting light. More specifically, the present invention relates to a planar light source unit for a color display device and a liquid crystal color display structure, which can obtain a uniform color display even when the display device is directly viewed nearby.

  Conventionally, when performing color display on a liquid crystal display panel or the like, as shown in FIG. 6A or FIG. 6B, each of the three primary colors red (R), green (G), and blue (B) is displayed. One dot 11 is composed of a set of pixels, and the intensity of red, green, and blue is changed to display a color for each dot 11 using a mixed color of three pixels. That is, in the case of a liquid crystal display panel, each color filter is provided on a transparent substrate corresponding to each pixel of red, green, and blue, and the color of light to be mixed is controlled by controlling the light transmitted through the pixel. The color display is performed by mixing colors. A considerable number of display devices using color filters have been proposed in addition to the following patent documents.

Japanese Patent Laid-Open No. 2003-315777 “Color Liquid Crystal Display Device”. wrap up. Claims. FIG. Japanese Patent Application Laid-Open No. 2002-40235 “Reflective color liquid crystal display element and color reflector”. wrap up. Claims. FIG.

As described above, in a conventional color display device that displays colors by providing a backlight on the back side of the display panel, three primary color filters of red, green, and blue are provided corresponding to the three adjacent pixels, respectively. In other words, a single color is used by utilizing a color mixing effect when the light of each color transmitted through the color filter is viewed from a distance. For this reason, a white light source having a certain luminance is required as a light source provided on the back side of the display panel as a backlight, and a semiconductor switching element is required to transmit and block light of mixed colors.

Furthermore, in this method, adjacent colors are mixed with the sense of eyes, so if each pixel is made fine, it can be recognized as a mixed color.However, if the pixel is large or the direct view position is very close to the display screen, color mixing is possible. This causes a problem that it is not recognized as a beautiful color display screen but is recognized as an individual color instead of a selected color.

The present invention solves such a problem, and in a color flat display device that arranges light sources on the front side or the back side of a display panel and displays an image by transmission or non-transmission of the light, pixels of three primary colors are arranged. A surface light source unit for a color display device and a liquid crystal color display capable of performing color display by controlling light emission of mixed colors in one pixel, instead of recognizing the mixed colors with the sense of eyes side by side The purpose is to provide a structure.

It is another object of the present invention to provide a planar light source unit for a color display device and a liquid crystal color display structure which can obtain a uniform color display even when the display device is directly viewed nearby.

  As a result of studying the above problems, the present inventor has reached the present invention. That is, the invention claimed in the present application as means for solving the above problems is as follows.

(1) A plurality of single-color light sources that emit light of different colors, a reflecting plate that reflects light emitted from the light source to make reflected light, and a light diffusion plate that receives the reflected light and transmits it A planar light source unit for a color display device that can be used as a planar light source for a color display device.
(2) A plurality of single color light sources capable of emitting light of different colors with variable brightness, and a wide angle capable of irradiating a certain area of the light diffusion plate described later by reflecting light emitted from the light source at a wide angle. It comprises a reflecting plate for reflecting light and a light diffusing plate that receives and transmits the reflected light, and a certain area of the light diffusing plate is irradiated with reflected light of different colors originating from all light sources. Accordingly, light of one color in which light of each color is mixed is generated in the fixed region, and the light diffusing plate can be used as a planar light source for a color display device. Planar light source unit for equipment.
(3) The planar light source unit for a color display device according to (1) or (2), wherein the light source is attached to a casing constituting the planar light source unit for the color display device. .
(4) The light source according to any one of (1) to (3), wherein three types of light that emit red (R), green (G), and blue (B) light are used. Planar light source unit for color display devices.
(5) The planar light source unit for a color display device according to any one of (1) to (4), wherein a light emitting diode (LED) is used as the light source.
(6) The planar light source unit for a color display device according to any one of 1) to (5), wherein the light diffusion plate is configured using a prism diffusion plate.
(7) A surface shape for a color display device according to any one of (1) to (6), characterized in that light source control means for controlling blinking and luminance change for each light source of each color is provided. Light source unit.

(8) A plurality of the planar light source units for a color display device according to any one of (1) to (7) are used and arranged in a matrix, and the one of the planar light source units extends over two or more planar light source units. A planar light source composite for a color display device, wherein a light diffusion plate is provided in common.

(9) A liquid crystal panel in which a plurality of pixels, each of which can control light transmission and non-transmission independently, are formed in a matrix, and each pixel is provided on the back side of the liquid crystal panel. 7) A liquid crystal color display structure comprising the planar light source unit for a color display device according to any one of 7).
(10) The liquid crystal panel in which a plurality of pixels, each of which can independently control transmission and non-transmission of light, are provided in a matrix, and each pixel is provided on the back side of the liquid crystal panel. A liquid crystal color display structure comprising: a planar light source composite for a color display device.

  Since the planar light source unit for a color display device and the liquid crystal color display structure of the present invention are configured as described above, according to this, a light source is arranged on the front surface side or the back surface side of the display panel to transmit the light, In a color flat display device that displays an image by impermeability, by arranging pixels of the three primary colors and recognizing the mixed color with the sense of eyes, by controlling the light emission of the mixed color by one pixel Color display can be made. In other words, it is suitable for backlights that emit light from the back side of display devices such as color liquid crystal panels and illuminated signboards, and color light-emitting lights that emit light from the front side, and even when viewing the display device nearby. Color display can be obtained.

That is, according to the present invention, the three primary colors of light are arranged side by side and the three pixels are not observed as one dot, but each pixel is observed by light of already mixed color or its transmitted light. A clear natural color display screen can be obtained without being observed in different colors that are not mixed depending on the viewing position.

Furthermore, since one color is formed by a plurality of light sources, even if one light source becomes defective, the entire screen is not turned off, and a stable display can be obtained.

Hereinafter, the present invention will be described in more detail with reference to the drawings.
FIG. 1 is an explanatory view showing in cross section the basic structure of a planar light source unit for a color display device of the present invention. In the figure, this unit 1 includes a plurality of single-color light sources 3A, 3B, etc. that emit light of different colors, a reflection plate 4 that reflects light emitted from the light sources 3A, etc. into reflected light, and the reflected light And a light diffusing plate 2 for transmitting the light (2). In the present invention, the number of the light sources 3A and the like is not particularly limited. Usually, three light sources each emitting three primary colors of red (R), green (G), and blue (B) are used. By using it, the object of the present invention can be fully achieved.

  In the figure, since the planar light source unit 1 for color display device has the above-described configuration, light of different colors is emitted from the single color light sources 3A, 3B, etc., and these lights are reflected by the reflecting plate 4. The reflected light is received by the light diffusing plate 2 and transmitted therethrough. Thereby, the light diffusing plate 2 can be used as a planar light source for a color display device.

  In the drawing, the configuration of the planar light source unit 1 for a color display device also includes a plurality of single-color light sources 3A, 3b, etc. capable of emitting light of different colors, and a wide angle from the light source 3A. A reflection plate 4 that reflects light emitted to irradiate a certain area of the light diffusion plate 2 to be described later and is a wide angle reflection light; and a light diffusion plate 2 that receives the reflection light and transmits it. (Invention (2) above). With this configuration, a certain area of the light diffusing plate 2 is irradiated with reflected light of different colors originating from all the light sources 3A and the like, and light of one color in which light of each color is mixed in the certain area is generated. Thus, the light diffusing plate 2 can be used as a planar light source for a color display device. As will be described later with reference to FIG. 4, each color is mixed by irradiating light having a wide angle range from one light source 3 </ b> A or the like to the reflection plate 4 to generate wide-angle reflected light. As a result, the reflected light is uniformly applied to the entire range or the wide range of the surface of the light diffusing plate 2, and this is similarly achieved for the light of each color.

In the figure, the light source 3A and the like can be configured to be attached to a housing 5 constituting the planar light source unit for a color display device (the invention of (3) above). As shown in the figure, the housing 5 has a three-dimensional structure under the conditions satisfying the above configuration so that the light diffusing plate 2 and the reflecting plate 4 are favorably reflected from the latter in the former direction. Further, the light source 3A and the like are further arranged so as to irradiate the reflecting plate 4 so as to generate good reflected light.

  FIG. 2 is a perspective view showing another configuration example of the planar light source unit for a color display device of the present invention. As shown in the figure, in this unit 11, three types of single-color light sources 13A, 13B, and 13C that emit red (R), green (G), and blue (B) light, respectively, are used as the light sources. Yes (invention (4) above).

In FIG. 2, in the planar light source unit 11 for the color display device of the present invention, a light emitting diode (LED) can be used as the light source 13A or the like (the invention of (5) above). The specifications / types / numbers of the light sources are not particularly limited. As shown in FIG. 2, a red LED, a green LED, and a blue LED are used as one of the light sources 13A, etc. Can be arranged side by side. For example, if it is a pixel of about 50 mm × 50 mm, an LED having a diameter of about 6 mm can be suitably used. It is also possible to use LED chips, which are smaller in size and advantageous in design.

By using an LED as the light source 13A, etc., it is easy to install in a narrow space, taking advantage of its small size, etc., and it can be driven at a low voltage and has a long life, so it has excellent maintainability. Can be a unit. In addition, since an LED can be loaded as a semiconductor chip, it is optimal for a planar light source for a small display screen. However, as described above, the light source according to the unit of the present invention is not limited to the LED. For example, a white light source such as an ordinary miniature light bulb that has a color filter attached thereto can be used preferably.

In FIG. 2, the planar light source unit 11 for the color display device of the present invention can also use a prism diffusion plate provided on one surface as the light diffusion plate 12 (the invention of (6) above). As the prism diffusion plate, a known one can be used as appropriate.

In FIG. 2, the planar light source unit 11 for a color display device of the present invention can also be provided with a light source control means (not shown) for controlling blinking and luminance change for each color light source ((7) above). Invention).

In FIG. 2, a transparent plate made of acrylic, polycarbonate, plastic, or the like made of a transparent resin that can easily reflect or transmit light can be suitably used as the reflecting plate 14, but it is particularly limited to the resin. However, if the inner surface is easily reflected by glass or the like, this can also be suitably used. The reason why the inner surface is easily reflected is to effectively use light from the light source 13A or the like. That is, the light emitted from the light source 13A or the like is reflected and radiated to the outside through the prism diffusion plate (12) as shown in FIG. By applying a white paint or the like to the back surface of the reflecting plate 14, the internal reflection efficiency is further improved, the light loss is reduced, and the reflection efficiency is improved.

FIG. 3 is a side view showing a light source configuration example of the planar light source unit for a color display device of the present invention. As illustrated in the figure, the LEDs may be arranged in such a manner that the red LEDs 23A, the green LEDs 23B, and the blue LEDs 23C are alternately arranged instead of arranging a plurality of light sources in a line as shown in FIG. In the present invention, the light having the desired color as a result of mixing the light from the light sources 23A and the like of the plurality of colors is directly viewed or used as a backlight.

FIG. 4 is an explanatory diagram for explaining the principle by which light from each light source is mixed in a reflector to obtain desired light. As shown in FIG. 4, for example, light emitted from the red LED 33 </ b> A is emitted over a wide angle in front. Then, the light is reflected by the reflecting plate 34 and proceeds in the direction of the prism diffusing plate 32. On the other hand, the light emitted from the green LED 33B and the blue LED 33C is similarly reflected by the reflecting plate 34 and travels in the direction of the prism diffusing plate 32. As a result, red, green, and blue light are reflected on the prism diffusing plate 32. The three colors are mixed, and a desired color can be obtained by controlling the intensity and blinking period of each light, and can be uniformly irradiated in the direction of the arrow as planar light emission from the surface of the prism diffusion plate 32. As described above, the light emitted from each light source 33A and the like can be designed to be emitted at a wide angle and uniformly irradiate the entire surface of the prism diffusion plate 32. The arrangement order and arrangement position of the LED 33B and the blue LED 33C are not particularly limited.

  FIG. 5 is a cross-sectional view illustrating a configuration example of a liquid crystal color display structure including the planar light source composite for a color display device of the present invention. The planar light source composite M for color display device shown in the lower part of the drawing is a matrix in which a plurality of planar light source units 41 for color display devices having any of the above-described configurations are used. And one of the light diffusion plates 42 is commonly provided across the two or more planar light source units 41 (the invention of (8) above).

Any one of the above-described planar light source units for a color display device or the planar light source complex M for a color display device as illustrated in FIG. 5 is configured by any of the above-described planar light source units for a color display device. A liquid crystal color display structure D can be configured by combining the above and a liquid crystal panel P in which a plurality of pixels, each of which can control transmission and non-transmission of light independently, are formed in a matrix (see (( 9) and invention of (10)).

As shown in the figure, the liquid crystal color display structure D includes transparent substrates 51 and 52 made of glass or the like, and transparent electrodes 53 and 54 provided on the transparent substrate 52 or the like (one is vertically and horizontally and the other is provided on the left and right). The crossing portion becomes a pixel, and the pixel is formed in a matrix shape). The liquid crystal injected between the sealing agent 57, the alignment films 55 and 56, and the two transparent electrodes for bonding the two transparent substrates 52 and the like. It is comprised from the material 58, the polarizing plates 59 and 60, etc., and these structures are the same structures as a normal liquid crystal panel. Unlike a conventional color display structure including a color filter, the color filter structure is not provided on the light output side, and the planar light source unit of the present invention is provided on the light input side. Further, the liquid crystal color display structure can be used as a full-color image display structure by including the control means capable of changing the luminance and blinking cycle of each light source in accordance with the information signal of each pixel.

In other words, the above-described planar light source unit for a color display device is arranged in accordance with each pixel of the flat display device, and a control unit is provided that can change the luminance and blinking cycle of each light source according to the information signal of each pixel. For example, an arbitrary emission color can be obtained for each pixel, and a full-color image display can be obtained. In this case, if the prism diffuser plate of the planar light source unit for the color display device arranged vertically and horizontally is made large by collecting a plurality of pieces, by creating only the reflector without the prism diffuser plate of the planar light source, It is possible to obtain a color planar light source for a flat display device in which planar light sources corresponding to each pixel are arranged vertically and horizontally.

In the drawing, a plurality of planar light source units 41 are provided so as to be positioned below the respective pixels. As a result, light of a color suitable for each pixel can be created for each pixel, and the light can be transmitted and viewed directly. Therefore, it is not a color mixture according to the sensation of eyes, but even when viewed close-up or on a large display screen and a liquid crystal device with a large number of display pixels per pixel, there is no color unevenness and a natural color display is achieved. Can do.

  According to the planar light source unit for a color display device and the liquid crystal color display structure of the present invention, a color plane type in which a light source is arranged on the front surface side or the back surface side of the display panel and an image is displayed by transmitting or not transmitting the light. In the display device, it is possible to display a color by controlling light emission of mixed colors in one pixel, instead of recognizing a color mixed with the sense of eyes by arranging pixels of three primary colors. In other words, it is suitable for backlights that emit light from the back side of display devices such as color liquid crystal panels and illuminated signboards, and color light-emitting lights that emit light from the front side, and even when viewing the display device nearby. Color display can be obtained.

That is, according to the present invention, the three primary colors of light are arranged side by side and the three pixels are not observed as one dot, but each pixel is observed by light of already mixed color or its transmitted light. A clear natural color display screen can be obtained without being observed in different colors that are not mixed depending on the viewing position. Further, since one color is formed by a plurality of light sources, even if one light source becomes defective, the entire screen is not turned off, and a stable display can be obtained, which is industrially applicable. It is a highly valuable invention.

It is explanatory drawing which shows the basic composition of the planar light source unit for color display apparatuses of this invention in a cross section. It is a perspective view which shows another structural example of the planar light source unit for color display apparatuses of this invention. It is a side view which shows the light source structural example of the planar light source unit for color display apparatuses of this invention. It is explanatory drawing explaining the principle by which the light from each light source is mixed in a reflecting plate, and desired light is obtained. It is sectional drawing which shows the structural example of the liquid crystal color display structure provided with the planar light source composite body for color display apparatuses of this invention. It is explanatory drawing which shows the principle of the conventional color display. It is explanatory drawing which shows the principle of the conventional color display.

Explanation of symbols

1, 11, 21, 31, 41 ... planar light source unit for color display device 2, 12, 22, 32, 42 ... light diffusion plate (prism diffusion plate)
3A, 3B ... single color light sources 13A, 13B, 13C ... light sources 23A, 23B, 23C ... light sources 33A, 33B, 33C ... light sources 4, 14, 34 ... reflectors 5, 25 ... casings 51, 52 ... transparent substrate 53, 54 ... Transparent electrodes 55, 56 ... Alignment film 57 ... Sealing agent 58 ... Liquid crystal material 59, 60 ... Polarizing plate M ... Planar light source composite P for color display device ... Liquid crystal panel D ... Liquid crystal color display structure

Claims (10)

A plurality of single-color light sources that emit light of different colors, a reflecting plate that reflects light emitted from the light source to make reflected light, and a light diffusion plate that receives the reflected light and transmits it Thus, a planar light source unit for a color display device, which can use the light diffusing plate as a planar light source for a color display device. A plurality of single color light sources capable of emitting light of different colors with variable brightness, and a wide angle reflected light capable of reflecting a light emitted from the light source at a wide angle and irradiating a predetermined area of a light diffusion plate described later; And a light diffusing plate that receives the reflected light and transmits it, and a certain area of the light diffusing plate is irradiated with reflected light of different colors originating from all light sources. A color display device surface characterized in that light of one color mixed with light of each color is produced in the fixed region, whereby the light diffusion plate can be used as a planar light source for a color display device Light source unit. The planar light source unit for a color display device according to claim 1, wherein the light source is attached to a casing constituting the planar light source unit for the color display device. 4. The color display device according to claim 1, wherein the light source includes three types that emit red (R), green (G), and blue (B) light, respectively. 5. Planar light source unit. The surface light source unit for a color display device according to any one of claims 1 to 4, wherein a light emitting diode (LED) is used as the light source. 6. The planar light source unit for a color display device according to claim 1, wherein the light diffusion plate is configured using a prism diffusion plate. 7. A planar light source unit for a color display device according to claim 1, further comprising light source control means for controlling blinking and luminance change for each color light source. A plurality of planar light source units for a color display device according to any one of claims 1 to 7 are used and arranged in a matrix, and one light diffusion plate is shared across two or more planar light source units. A planar light source composite for a color display device, wherein the planar light source composite is provided. 8. A liquid crystal panel in which a plurality of pixels, each of which can control light transmission and non-transmission independently, are formed in a matrix, and each pixel is provided on the back side of the liquid crystal panel. A liquid crystal color display structure comprising: a planar light source unit for a color display device as described in 1 above. 8. A color display according to claim 7, wherein a plurality of pixels, each of which can control light transmission and non-transmission independently, are formed in a matrix, and each pixel is provided on the back side of the liquid crystal panel. A liquid crystal color display structure comprising: a planar light source composite for a device.

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