Image display device
View Patent ↗A multi-color display system operates to suppress deterioration in resolution and increase in power consumption or deterioration in brightness. The multi-color display system includes n types of spectrum selecting means; m types of light sources each having a different spectral distribution; light source controlling means for controlling, on a time-division basis, emissions from the m types of light sources; color light sources controlled by the light source controlling means and the n types of spectrum selecting means, the number of the color light sources being not less than n+1, but not more than n×m; and a light valve for controlling transmittance or reflectance of light in accordance with image information.
1. An image display device comprising:
a pair of transparent substrates;
a liquid crystal composition and at least two types of color filters disposed between said pair of substrates;
at least two types of light sources, each of said light sources having an emission distribution which is different from one another, and each of said light sources generating peak wavelengths of at least three colors; and
light source controlling means for switching on and off said light sources, which generate peak wavelengths of said at least three colors, in time sequence within one frame period.
2. The image display device according to claim 1 , wherein a shape formed by coordinates on a chromaticity diagram for output light, which is generated by the display device, is a closed figure of at least four sides and having a vertex which is in the shape of a convexity.
3. The image display device according to claim 1 , wherein three types of color filters are provided.
4. The image display device according to claim 3 , wherein a wavelength band to be selected depending on each of the color filters includes a maximum value of brightness of the peak wavelength of color, and a band of each of the peak wavelength is narrower than the wavelength band of each of the color filters.
5. The image display device according to claim 1 , further comprising a function for switching between a mode for lighting all the types of light sources and a mode for selectively lighting the light sources.
6. The image display device according to claim 1 , wherein the image display device is an active matrix type liquid crystal display device.
7. The image display device according to claim 6 , wherein display voltages are written for all the pixels when the light sources for irradiating the active matrix type liquid crystal display device are not lit.
8. The image display device according to claim 7 , wherein the active matrix type liquid crystal panel device has a function of changing display of all the pixels simultaneously.
9. The image display device according to claim 8 , further comprising
a memory for storing image data in each of the pixels in the liquid crystal panel device in the format of digitized information obtained by converting a voltage value or multivalue; and
a strobe function for writing a voltage or a current value to each of the pixels in accordance with the information stored in the memory;
whereby the function of changing all the pixels simultaneously is achieved.
10. The image display device according to claim 6 , wherein a plurality of array light sources is aligned in a scanning direction for image rewriting of the active matrix type liquid crystal display device, and lighting of the light sources are scrolled in synchronization with the rewrite scanning.
11. The image display device according to claim 1 , wherein a display mode of the liquid crystal is an inplane switching mode.
12. The image display device according to claim 1 , wherein each of the light sources is a laser light source or an emission diode.
13. The image display device according to claim 1 , wherein each of the light sources is a light source that uses an emission generated by irradiating a fluorescent material with ultraviolet rays.
14. The image display device according to claim 1 , wherein a spectral wavelength or a spectral distribution of each of the light sources to be used for image display is controlled based on instructions from a viewer of the image display device, light source information on a location where an image is captured, instructions from a creator of the image, or light source information on a location where the image display device is viewed.
15. The image display device according to claim 1 , wherein the number of the light sources is two, and each of the light sources generates peak wavelengths of three colors.
16. The image display device according to claim 1 , wherein the one frame period includes at least two sub-frames controlled in a time-division basis.
17. The image display device according to claim 1 , wherein the light source controlling means is responsive to instruction of a viewer of the image display device.
18. The image display device according to claim 1 , wherein the at least two types of light sources are arranged in a direction of rewrite scanning, the light sources being controlled in accordance with the rewrite scanning.
19. The image display device according to claim 2 , wherein the closed figure of at least four sides is a hexagon.