Light sensitive display

• US 20080055498A1
• Filed: 10/26/2007
• Published: 03/06/2008
• Est. Priority Date: 05/23/2002
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Abileah, Adiel, Green, Pat, Boer, Willem
• Granted Patent: US 9,354,735 B2
• Time in Patent Office: Days
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13312 Circuits comprising photodetectors for purposes other than feedback
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G06F 2203/04109 FTIR in optical digitiser, i.e. touch detection by frustrating the total internal reflection within an optical waveguide due to changes of optical properties or deformation at the touch location
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/042 by opto-electronic means
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A light sensitive display.

Claims

1. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer comprising a plurality of pixel electrodes;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a light guide together with an associated light source located in front of said front electrode layer to provide light thereto;

(f) a plurality of light sensitive elements located within said display;

(g) a processor determining the location of touching of said display by sensing a light inhibited region relative to the ambient surroundings by said light sensitive elements wherein light has been inhibited from reaching said light sensitive elements with an interior region to said inhibited region having greater illumination.

2. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer comprising a plurality of pixel electrodes;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a plurality of light sensitive elements located within said display;

(f) a processor determining the location of touching of said display by sensing a light inhibited region relative to the ambient surroundings by said light sensitive elements wherein light has been inhibited from reaching said light sensitive elements with an interior region to said inhibited region having greater illumination.

3. A light sensitive display comprising:

(a) said display selectively causing pixels to provide light;

(b) a plurality of light sensitive elements located within said display;

(c) a processor that receives information from said light sensitive elements and determines regions of said display relative to ambient surroundings where ambient light is inhibited from reaching said light sensitive elements, wherein data from said light sensitive elements is temporally analyzed.

4. The display of claim 3 wherein said temporal analysis determines whether a pointing device is “

hovering”

with respect to said display or touching said display.

5. The display of claim 3 wherein said temporal analysis determines whether a pointing device remains stationary for a period of time.

6. The display of claim 3 wherein said temporal analysis determines whether a pointing device approaches the display and thereafter recedes from the display.

7. The display of claim 6 wherein the general time between approaching and receding is used as a basis for said pointing device touching said display.

8. The display of claim 3 wherein said temporal analysis determines whether a pointing device approaches said display and said pointing device maintains the same general size, where the general time when the shadow maintains the same size is used as a basis for said pointing device touching said display.

9. The display of claim 3 wherein said display is a liquid crystal display.

10. The display of claim 3 wherein said liquid crystal display is active matrix.

11. The display of claim 3 wherein said liquid crystal display is passive.

12. A light sensitive display comprising:

(a) said display selectively causing pixels to provide light;

(b) a plurality of light sensitive elements located within said display;

(c) a sampling circuit that reads data from said plurality of light sensitive elements at a rate corresponding with the refresh rate of the corresponding portion of said display, wherein the display includes at least two different refresh rates;

(d) a readout system determining when the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light, whereby said readout system distinguishes between ambient surroundings and said at least one of said plurality of light sensitive elements said inhibited from sensing said ambient light.

13. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer comprising a plurality of pixel electrodes;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a plurality of light sensitive elements located within said display;

(f) a light guide together with an associated light source located in front of said front electrode layer to provide light thereto, wherein said light has a color spectrum less than ambient light; and

(g) a color filter positioned between said light guide and at least one of said light sensitive elements, wherein said color reduces the transmission of said ambient light to an extent greater than said light from said light source.

14. The device of claim 13 wherein said ambient light is white light.

15. The device of claim 13 wherein said color filter has a transmission of said ambient light less than 75%.

16. The device of claim 13 wherein said color filter has a transmission of said ambient light less than 60%.

17. The device of claim 13 wherein said color filter has a transmission of said ambient light less than 50%.

18. The device of claim 13 wherein said color filter has a transmission of said ambient light less than 40%.

19. The device of claim 13 wherein said color filter has a transmission of said ambient light less than 30%.

20. The device of claim 13 wherein said color filter has a transmission of said light from said light source greater than 25%.

21. The device of claim 13 wherein said color filter has a transmission of said light from said light source greater than 40%.

22. The device of claim 13 wherein said color filter has a transmission of said light from said light source greater than 50%.

23. The device of claim 13 wherein said color filter has a transmission of said light from said light source greater than 60%.

24. The device of claim 98 wherein said color filter has a transmission of said light from said light source greater than 70%.