JP2001356318A - Color liquid crystal display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color liquid crystal display system by which higher color saturation is obtained and, also, white is expressed clearly even when the luminance of a back light is used by being lowered and description having a high contrast is possible. SOLUTION: Color liquid crystal display is performed by applying modulation by a video signal of only a red frame to liquid crystal module electrodes when the back of the liquid crystal module is irradiated with the monochromatic light source of red color and by repeating the same processing as to a next green color and a succeeding blue color.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a color liquid crystal display system.

[0002]

2. Description of the Related Art A liquid crystal display device has rapidly advanced technically among display devices, and its space saving property is superior to that of a CRT, and its depiction is approaching that of a CRT. For this reason, liquid crystal display devices that have been conventionally used only for devices that place emphasis on portability are replacing the display devices of desktop personal computers and home TVs with CRTs.

FIG. 6 is a schematic diagram showing the operation principle of a conventional backlight type liquid crystal display device. In FIG. 6, white light 601 from a backlight (not shown) is shown.
Shows a process of sequentially passing through the polarizing layer 602, the liquid crystal layer 603 to which the voltage 604 modulated by the video signal is applied, and the polarizing layer 605, and the dot or segment based on the video signal becomes the image 606. That is, by applying a video signal to the liquid crystal layer 603, the transmittance of the liquid crystal layer of the light is changed to adjust the individual dot or segment luminance, and the video signal is converted into an image or a character so that it can be visually displayed. I do.

[0004] In color display, white light including three components R, G and B of light color is applied to these dots.
As shown in FIG. 5, R (501), G (50
2), B (503) By arranging the color filters in each column, light of a specific hue element is transmitted to express a color. In the example of FIG. 5, the left vertical line of the character N is displayed in green, the diagonal line is displayed in red, and the right vertical line is displayed in blue.

[0005]

However, in the conventional method, there is a part of the detail of the descriptive power which is not yet comparable to that of the CRT. One of the parts is that it is difficult to emit light of only the absolutely desired color element. Another problem is that, when the backlight is used with reduced luminance, contrast characteristics deteriorate because white cannot be clearly expressed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides a higher color saturation, expresses white clearly even when the backlight is used with reduced luminance, and has a high contrast. It is an object of the present invention to provide a color liquid crystal display system capable of depiction.

[0007]

According to a first aspect of the present invention, there is provided a color liquid crystal display system using a backlight which is lit by monochromatic light of red, green and blue in a backlight type liquid crystal display device. The three types of individually adjusted monochromatic lights are sequentially turned on and off in synchronization with the frequency of the divided video frame.

According to the color liquid crystal display system of the first aspect,
When a liquid crystal module is modulated by a red video signal, the red backlight lights up and red information is visually recognized. Similarly, green information and blue information are sequentially recognized for green and blue, and the video signal is displayed in color to human eyes. I can see Further, since the luminance of each color of red, green, and blue can be individually adjusted, the adjustment of the hue is easy.

According to a second aspect of the present invention, in a liquid crystal display device using a backlight system, red, green, and blue light emitting diodes are arranged in a row, and the light emitting diode rows are repeatedly arranged in the order of red, green, and blue. By providing a striped light emitting diode array, a cylindrical concave Fresnel lens is arranged on the front surface of the light emitting diode array, a cylindrical convex Fresnel lens is arranged on the front surface, and a liquid crystal module is arranged on the foreground. And

According to the color liquid crystal display system of the second aspect,
The entire surface of the liquid crystal module can be illuminated in chronological order with monochromatic light of red, green, and blue.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a configuration of a liquid crystal display device of the present invention, and FIG. 2 shows an example of a display state of the liquid crystal. FIG. 3 shows an embodiment of a backlight structure for enabling the present invention.

In FIG. 1, reference numeral 101 denotes a liquid crystal module,
102 is a video signal to be displayed on the liquid crystal module 101,
Reference numeral 103 denotes the video signal 102 as R (red), G (green), B
A frame memory decomposed for each frame of (blue) is shown. Reference numeral 104 denotes a backlight, and a red monochromatic light source 106 and a green monochromatic light source 1 corresponding to R, G, and B frames.
07, a switch 105 for sequentially turning on the blue monochromatic light source 108, and the luminous flux of the red, green, and blue monochromatic light sources so that the light of each emission color uniformly irradiates the entire back surface of the liquid crystal module 101. Beam rectifier 109 for rectification
Contains. Here, it is appropriate to set the switching frequency of the three monochromatic lights from 60 Hz to 80 Hz in consideration of the characteristics of human eyes. Red monochromatic light source 106
When the back surface of the liquid crystal module 101 is illuminated, the liquid crystal module electrode is modulated by the video signal of only the red frame, and the next green monochromatic light source 107 causes the liquid crystal module 1 to emit light.
01, the liquid crystal module electrode is modulated by the video signal of only the green frame, and when the back surface of the liquid crystal module 101 is subsequently illuminated by the monochromatic blue light source 108, the liquid crystal module electrode is modulated by the video signal of only the blue frame. The color liquid crystal display is performed by synchronizing the repetition of returning to red again with the switching frequency.

FIG. 2 shows an example in which the letter N is displayed in color. Reference numeral 201 denotes a left vertical bar when irradiating the back surface of the liquid crystal module with green monochromatic light; 202, an oblique bar when irradiating the back surface of the liquid crystal module with red monochromatic light; The liquid crystal in the right vertical bar portion when the back surface of the liquid crystal module is illuminated with blue monochromatic light sequentially emits light in chronological order, and N characters are displayed in three colors by the afterglow characteristics of the eyes.

FIG. 3 is a partial structural view for uniformly irradiating the light of each emission color of the red, green and blue monochromatic light sources over the entire back surface of the liquid crystal module. Reference numeral 301 denotes a monochromatic red light source, 302 denotes a monochromatic green light source, and 303 denotes a monochromatic light source. Blue monochromatic light source, 3
04 is a light diffusion lens group, 305 is a light focusing lens group, 30
Reference numeral 6 denotes an image of a light beam, and reference numeral 307 denotes dots of the liquid crystal module. Here, as an element used for each of the monochromatic light sources 301, 302, and 303, an electroluminescence, a plasma light emitting element, a laser light emitting element, and the like can be used in addition to the light emitting diode.

FIG. 4 is a perspective view of an embodiment in which FIG. 3 is expressed in a plane, wherein 401 is a three-color striped light emitting diode array, 402 is a cylindrical concave Fresnel lens, 403 is a cylindrical convex Fresnel lens, 40
Reference numeral 4 denotes a liquid crystal module.

[0016]

According to the present invention, since the luminance can be adjusted for each of the three primary colors of light, higher chroma can be obtained, and
Even if the brightness of the backlight is reduced, white can be clearly expressed and high-contrast depiction is possible. Also,
Conventionally, complicated hue correction has been performed in a liquid crystal color display, but hue correction can be easily performed only by adjusting the luminance of three types of monochromatic light, similarly to a CRT.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a liquid crystal display system of the present invention.

FIG. 2 is an example of a display state of the liquid crystal of the present invention.

FIG. 3 is a partial side view of an embodiment of a backlight structure according to the present invention.

FIG. 4 is a perspective view showing one embodiment of a backlight type liquid crystal display device of the present invention.

FIG. 5 is a display example of a conventional liquid crystal.

FIG. 6 is a schematic view showing the operation principle of a conventional backlight type liquid crystal display device.

[Explanation of symbols]

Reference Signs List 101 liquid crystal module 102 video signal 103 frame memory for decomposing video signal into R, G, B frames 104 backlight 105 switcher 106 monochromatic red light source 107 monochromatic green light source 108 monochromatic blue light source 109 luminous flux rectifier 201 monochromatic monochromatic green light , N-character left vertical line when illuminating the back of the liquid crystal module 202 N-character oblique line when illuminating the back of the liquid crystal module with monochromatic red light 203 N-character right vertical line when illuminating the back of the liquid crystal module with monochromatic blue light 301 Red monochromatic light source 302 Light source 303 Blue monochromatic light source 304 Light diffusing lens group 305 Light focusing lens group 306 Image of light flux 307 Dot of liquid crystal module 401 Tricolor striped light emitting diode array 402 Cylindrical concave Fresnel lens 403 Cylindrical convex Fresnel lens 40 Liquid crystal module 501 Red (R) liquid crystal module dot row 502 Green (G) liquid crystal module dot row 503 Blue (B) liquid crystal module dot row 601 White light from backlight 602 Polarizing layer 603 Liquid crystal layer 604 Modulated by video signal Voltage 605 polarizing layer 606 image

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 3/20 642 G09G 3/20 650M 650 3/34 J 3/34 3/36 3/36 G02F 1 / 1335 530 F-term (reference) 2H091 FA26Z FA45Z FD01 FD03 FD24 GA11 LA15 LA17 2H093 NA65 NC44 ND04 ND17 ND24 5C006 AA22 AC21 AF01 AF22 AF23 AF44 AF69 BB11 BF02 EA01 FA56 5C080 AA10 BB05 EJ05 A03 BB05 CC03 DD01 DD03 DD03 DD03 BB12 BB15 CC09 CC12 EE26 EE30 FF11 GG05 GG23 GG26 GG27

Claims (2)

[Claims] 1. A liquid crystal display device using a backlight system, wherein a backlight that is lit by monochromatic light of red, green, and blue is used, and the three types are synchronized with the frequency of a video frame divided into red, green, and blue. A color liquid crystal display system characterized by sequentially blinking monochromatic light whose brightness is individually adjusted. 2. In a backlight type liquid crystal display device, red, green, and blue light-emitting diodes are arranged in a line, and the light-emitting diode lines are repeatedly arranged in the order of red, green, and blue to form a striped light emission. 2. The color according to claim 1, wherein a diode array is provided, a cylindrical concave Fresnel lens is arranged on the front surface of the light emitting diode array, a cylindrical convex Fresnel lens is arranged on the front surface, and a liquid crystal module is arranged on the top surface. Liquid crystal display system.