ENERGY EFFICIENT TRANSFLECTIVE DISPLAY

• US 20080002095A1
• Filed: 05/25/2007
• Published: 01/03/2008
• Est. Priority Date: 05/25/2006
• Status: Active Grant

• Current Assignee: I2IC Corporation
• Original Assignee: I2IC Corporation
• Inventors: Kanade, Udayan, Ganapathy, Balaji
• Granted Patent: US 8,089,580 B2
• Time in Patent Office: Days
• US Class Current: 349/62
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors

Abstract

An energy efficient transflective display system is disclosed. In one embodiment, the system comprises a reflector sheet and a transparent backlight sheet placed in front of the reflector sheet. A display panel is placed in front of the transparent backlight sheet where the display panel has a light valve.

Claims

1. An apparatus, comprising

a reflector sheet,

a transparent backlight sheet placed in front of the reflector sheet, and

a display panel placed in front of the transparent backlight sheet, the display panel having a light valve.

2. The apparatus of claim 1, further comprising color filters.

3. The apparatus of claim 1, wherein the light valve comprises a liquid crystal sheet situated between polarizer sheets.

4. The apparatus of claim 1, wherein the reflector sheet includes one or more of:

a metallic surface, a distributed Bragg reflector, a hybrid reflector, a total internal reflector, an omni-direction reflector, and a scattering reflector.

5. The apparatus of claim 1, further comprising a partial mirror sheet placed between the display panel and the transparent backlight sheet.

6. The apparatus of claim 1, further comprising a manual control that adjusts backlight power.

7. An apparatus, comprising

a reflector sheet,

a multicolored illuminator sheet placed in front of the reflector sheet,

a display panel placed in front of the multicolored illuminator sheet, the display panel having a light valve.

8. The apparatus of claim 7, further comprising color filters.

9. The apparatus of claim 7, wherein the light valve comprises a liquid crystal sheet situated between polarizer sheets.

10. The apparatus of claim 7, wherein the reflector sheet includes one or more of:

a metallic surface, a distributed Bragg reflector, a hybrid reflector, a total internal reflector, an omni-direction reflector, and a scattering reflector.

11. The apparatus of claim 7, further comprising a partial mirror sheet placed between the display panel and the transparent backlight sheet.

12. The apparatus of claim 7, further comprising a manual control that adjusts backlight power.

13. A method comprising:

sensing an ambient light intensity, and

adjusting a backlight power as a function of the ambient light intensity.

14. A method comprising:

calculating a value of a transmittance of a light valve as a function of ambient light intensity, backlight intensity and desired illumination at the light valve, and

changing the transmittance of the light valve according to the value.

15. The method of claim 14, wherein calculating the value of the transmittance is accomplished with electronic circuits.

16. The method of claim 14, wherein calculating the value of the transmittance is accomplished computationally in software.

17. The method of claim 14, wherein changing the transmittance of the light valve comprises changing an excitation voltage of liquid crystal present in the light valve.