TRANSFLECTIVE DISPLAY

• US 20100014032A1
• Filed: 07/15/2009
• Published: 01/21/2010
• Est. Priority Date: 07/16/2008
• Status: Active Grant

• Current Assignee: John Gilmore
• Original Assignee: Pixel Qi Corporation
• Inventors: Jepsen, Mary Lou
• Granted Patent: US 8,264,645 B2
• Time in Patent Office: Days
• US Class Current: 349/114
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G09G 2300/0456 with a reflective area and a transmissive area combined in one pixel, such as in transflectance pixels
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines

Abstract

A multi-mode Liquid Crystal Display (LCD) capable of functioning in a multi-mode, a monochrome reflective mode and a color transmissive mode. One embodiment provides an LCD with color filters only over most or all of the transmissive part of a pixel but only part of the reflective portion of a pixel, enabling readability in the ambient light. Embodiments eliminate the black matrix mask used typically in color filter creation. Additionally, an embodiment provides diagonal pixels to improve the resolution of the LCD in the color transmissive mode. Further, an embodiment enables the light to switch between two colors, while a third color (typically green) is always on, thereby decreasing the required frame rate of the LCD, when used in the hybrid field sequential approach. Yet another embodiment creates colors from the backlight, eliminating the need for color filters. Another embodiment involves use of color filters over only the green pixels, eliminating the need for using additional masks for making the color filter array.

Claims

1. A multi-mode Liquid Crystal display, comprising:

a light source for illuminating the multi-mode display;

a first polarizer for aligning the plane of polarization of light from the light source to a first plane;

a second polarizer for aligning the plane of polarization of the light from the light source to a pre-defined second plane;

a first substrate and a second substrate, the first substrate and the second substrate being interposed between the first polarizer and the second polarizer; and

a plurality of pixels, each of the plurality of pixels being positioned at the first substrate, each of the plurality of pixels comprising a reflective part and a transmissive part, wherein the reflective part has only part of a color filter, and at least part of the transmissive part comprises one or more color-filters that mostly or completely cover the transmissive part of the pixel.

2. The multi-mode Liquid Crystal Display according to claim 1, wherein the reflective part occupies opposite corners of the plurality of pixels.

3. The multi-mode Liquid Crystal Display according to claim 1, wherein the color filter associated with the reflective part of the pixel creates a monochrome white point for the entire pixel.

4. The multi-mode Liquid Crystal Display according to claim 1, wherein the transmissive part occupies a center of the plurality of pixels.

5. The multi-mode Liquid Crystal Display according to claim 1, wherein a spectrum of color is generated from the light from the light source using a diffractive or a micro-optical film.

6. The multi-mode Liquid Crystal Display according to claim 1, wherein the transmissive part is diagonally arranged.

7. The multi-mode Liquid Crystal Display according to claim 1, wherein the one or more color-filters are of different thicknesses.

8. The multi-mode Liquid Crystal Display according to claim 1, wherein the one or more color-filters are of a same thickness.

9. The multi-mode Liquid Crystal Display according to claim 1 further comprising one or more colorless spacers placed over the reflective part.

10. The multi-mode Liquid Crystal Display according to claim 9 wherein the one or more colorless spacers are of a same thickness.

11. The multi-mode Liquid Crystal Display according to claim 1 wherein the one or more colorless spacers are of different thicknesses.

12. The multi-mode Liquid Crystal Display according to claim 1 further comprising a driver circuit to provide pixel values to a plurality of switching elements, wherein the plurality of switching elements determines the light transmitting through the transmissive part.

13. The multi-mode Liquid Crystal Display according to claim 12, wherein the driver circuit further comprises a Transistor-Transistor-Logic interface.

14. The multi-mode Liquid Crystal Display according to claim 12 further comprising a timing control circuit to refresh the pixel values of the multi-mode Liquid Crystal Display.

15. The multi-mode Liquid Crystal Display according to claim 12 wherein 1% to 50% of the reflective part has a color filter.

16. A computer, comprising:

one or more processors;

a multi-mode Liquid Crystal display coupled to the one or more processors and comprising a light source for illuminating the multi-mode display;

a first polarizer for aligning the plane of polarization of light from the light source to a first plane;

a second polarizer for aligning the plane of polarization of the light from the light source to a pre-defined second plane;

a first substrate and a second substrate, the first substrate and the second substrate being interposed between the first polarizer and the second polarizer; and

a plurality of pixels, each of the plurality of pixels being positioned at the first substrate, each of the plurality of pixels comprising a reflective part and a transmissive part, wherein the reflective part has only part of a color filter, and at least part of the transmissive part comprises one or more color-filters that mostly or completely cover the transmissive part of the pixel.

17. The computer of claim 16, wherein the reflective part occupies opposite corners of the plurality of pixels.

18. The computer of claim 16, wherein the color filter associated with the reflective part of the pixel creates a monochrome white point for the entire pixel.

19. The computer of claim 16, wherein the transmissive part occupies a center of the plurality of pixels.

20. The computer of claim 16, wherein a spectrum of color is generated from the light from the light source using a diffractive or a micro-optical film.

21. The computer of claim 16, wherein the transmissive part is diagonally arranged.

22. A multi-mode Liquid Crystal Display comprising a plurality of pixels, each of the plurality of pixels being positioned at a first substrate, each of the plurality of pixels comprising a reflective part and a transmissive part, wherein a first color filter is over only part of the reflective part, and the transmissive part comprises one or more second color-filters that mostly or completely cover the transmissive part of the pixel.