Transmissive color liquid crystal display

• US 20020080105A1
• Filed: 12/05/2001
• Published: 06/27/2002
• Est. Priority Date: 12/27/2000
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Sato, Tsuneo, Furuki, Ichiro, Yamada, Keiki, Takahashi, Masatoshi
• Granted Patent: US 6,690,348 B2
• Time in Patent Office: Days
• US Class Current: 345/87
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/133618 for ambient light
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/133622 Colour sequential illumination
• CPC Class Codes: G02F 1/133626 providing two modes of illumination, e.g. day-night
• CPC Class Codes: G09G 2300/02 Composition of display devices
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

A transmissive color liquid crystal display including a first liquid crystal section, a light-guiding element, a second liquid crystal section, and first and second liquid crystal drivers. The first liquid crystal section presents color images. The light-guiding element is situated behind the first liquid crystal section for orienting rays toward the first liquid crystal display section. The second liquid crystal section includes a plurality of zones capable of transmitting wavelength bands of external rays, respectively. The zones are selectively activated for introducing colored external rays through respective zones to the light-guiding element. The first liquid crystal driver controls the first liquid crystal section. While color-component data extracted from full color image data is input into the first liquid crystal driver in a time-division manner, the first liquid crystal driver activates and deactivates pixels on the first liquid crystal section for presenting images on the first liquid crystal display on the basis of the color-component data in time division manner. The second liquid crystal driver selectively activates the zones in the second liquid crystal section in time division manner for introducing colored external rays of which wavelength bands correspond to the color-component data through the zone to the light-guiding element for irradiating the images on the first liquid crystal section with the colored external rays in time division manner.

Claims

1. A transmissive color liquid crystal display comprising:

a first liquid crystal section for presenting color images;

a light-guiding element situated behind the first liquid crystal section for orienting rays toward the first liquid crystal section;

a second liquid crystal section including a plurality of zones capable of transmitting wavelength bands of external rays, respectively, the zones being selectively activated for introducing colored external rays through respective zones to the light-guiding element;

a first liquid crystal driver for controlling the first liquid crystal section, color-component data extracted from full color image data being input into the first liquid crystal driver in a time-division manner, the first liquid crystal driver activating and deactivating pixels on the first liquid crystal section for presenting images on the first liquid crystal display section on the basis of the color-component data in time division manner; and

a second liquid crystal driver for controlling the second liquid crystal section, the second liquid crystal driver selectively activating the zones in the second liquid crystal section in time division manner for introducing colored external rays of which wavelength bands correspond to the color-component data through the zone to the light-guiding element for irradiating the images on the first liquid crystal section with the colored external rays in time division manner.

2. The transmissive color liquid crystal display according to claim 1, wherein the first and second liquid crystal sections are parts of a single liquid crystal display panel assembly, the zones of the second liquid crystal sections being respectively provided with color filters capable of selectively transmitting color components of external rays, each of the color components having a wavelength band corresponding to the color-component data, whereby one of the color components are admitted through one of the zones and one of the color filters on the zone when the zone is activated by the second liquid crystal driver.

3. The transmissive color liquid crystal display according to claim 1, further comprising a prism for dispersing external rays into visible spectrum exhibiting color components, the spectrum resulting from external rays by the prism striking the second liquid crystal section, whereby one of the color components are admitted through one of the zones of the second liquid crystal section when the zone is activated by the second liquid crystal driver.

4. The transmissive color liquid crystal display according to claim 3, further comprising a slit plate facing to the second liquid crystal section, the slit plate being provided with a plurality of apertures of which the positions respectively correspond to the zones of the second liquid crystal section, whereby one of the color components are admitted through one of the apertures and one of the zones of the second liquid crystal section when the zone is activated by the second liquid crystal driver.

5. The transmissive color liquid crystal display according to claim 3, further comprising a third liquid crystal section activated for introducing external rays through the third liquid crystal section to the prism, and a third liquid crystal driver for controlling the third liquid crystal section, the first and third liquid crystal sections being parts of a single liquid crystal display panel assembly.

6. The transmissive color liquid crystal display according to claim 1, further comprising a light source unit disposed near the light-guiding element, the light source unit capable of emitting colored internal rays, of which wavelength bands correspond to the color-component data, introduced to the light-guiding element for irradiating the images on the first liquid crystal section with the colored external rays in a time division manner.

7. The transmissive color liquid crystal display according to claim 6, further comprising a battery charge monitor for detecting remaining charge of a battery for driving the transmissive color liquid crystal display, and an external-ray controller for controlling to use external rays when the battery charge monitor detects that the remaining charge is less than the threshold.

8. The transmissive color liquid crystal display according to claim 2, further comprising a light source unit and a half-mirror, the light source unit being positioned at the same side of the light-guiding element as that where the second liquid crystal section is positioned, the light source unit being disposed near the light-guiding element, the light source unit capable of emitting colored internal rays, of which wavelength bands correspond to the color-component data, introduced to the light-guiding element for irradiating the images on the first liquid crystal section with the colored external rays in a time division manner, the half-mirror being situated between the light-guiding element and the light source unit, the half-mirror reflecting external rays, which have passed through the second liquid crystal section, toward the light-guiding element and transmitting internal rays emitted from the light source unit toward the light-guiding element.

9. The transmissive color liquid crystal display according to claim 6, further comprising a light detector for measuring a sum of intensity of internal rays and external rays of each color component within the light-guiding element, and a light intensity optimizer for controlling the light source unit on the basis of the sum of the intensity measured by the light detector, so as to adjust the intensity of internal rays.

10. The transmissive color liquid crystal display according to claim 6, further comprising a light detector for measuring a sum of intensity of internal rays and external rays of each color component within the light-guiding element, and a light intensity optimizer for controlling the second liquid crystal section on the basis of the sum of the intensity measured by the light detector, so as to adjust the intensity of introduced external rays.

11. The transmissive color liquid crystal display according to claim 6, wherein the light-guiding element includes a first light-guiding element, to which internal rays are admitted, and a second light-guiding element, to which external rays are admitted, the transmissive color liquid crystal display further comprising a reflection film mounted on a side end surface of the first light-guiding element opposing to a side to which internal rays are admitted.

12. The transmissive color liquid crystal display according to claim 11, wherein the first liquid crystal section is situated in front of the first light-guiding element while the first light-guiding element is situated in front of the second light-guiding element.

13. The transmissive color liquid crystal display according to claim 11, wherein the first liquid crystal section is situated in front of the second light-guiding element while the second light-guiding element is situated in front of the first light-guiding element.

14. The transmissive color liquid crystal display according to claim 12, further comprising a half-mirror situated between the first light-guiding element and the second light-guiding element, the half-mirror reflecting internal rays admitted to the first light-guiding element and transmitting external rays admitted to the second light-guiding element.

15. The transmissive color liquid crystal display according to claim 13, further comprising a half-mirror situated between the first light-guiding element and the second light-guiding element, the half-mirror reflecting external rays admitted to the second light-guiding element and transmitting internal rays admitted to the first light-guiding element.

16. The transmissive color liquid crystal display according to claim 6, wherein the light source unit includes a plurality of linear light sources.

17. The transmissive color liquid crystal display according to claim 6, wherein the light source unit includes a plurality of point light sources.

18. The transmissive color liquid crystal display according to claim 6, wherein the light source unit includes a plurality of surface light sources.

19. A transmissive color liquid crystal display comprising:

a liquid crystal display panel assembly including an image display section for presenting color images and an external-ray transmissive section activated for introducing external rays through the external-ray transmissive section to the light-guiding element;

a light-guiding element situated behind the image display section for orienting rays toward the image display section;

a first liquid crystal driver for controlling the image display section, color-component data extracted from full color image data being input into the first liquid crystal driver in a time-division manner, the first liquid crystal driver activating and deactivating pixels on the image display section for presenting images on the image display section on the basis of the color-component data in time division manner;

a second liquid crystal driver for activating the external-ray transmissive section for introducing external rays through the external-ray transmissive section; and

a color selecting mechanism for selecting colors of external rays in time division manner for introducing colored external rays of which wavelength bands correspond to the color-component data to the light-guiding element for irradiating the images on the image display section with the colored external rays in time division manner.