Color liquid crystal display employing dual cells driven with an EXCLUSIVE OR relationship

• US 5,371,618 A
• Filed: 01/05/1993
• Issued: 12/06/1994
• Est. Priority Date: 01/05/1993
• Status: Expired due to Fees

• Current Assignee: Brite-Line Technologies Incorporated
• Original Assignee: Brite-Line Technologies Incorporated
• Inventors: Zou, Han, Tai, Chen-Yu
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Parker, Kenneth
• Application Number:
  US08/000,470
• Time in Patent Office: 700 Days
• Field of Search: 359/53, 359/84, 359/85, 359/41, 359/66, 345/87, 345/88, 345/4, 345/98, 345/100, 353/30, 353/31
• US Class Current: 349/78
• CPC Class Codes: G02F 1/13473 for wavelength filtering or for colour display without the use of colour mosaic filters

Abstract

A liquid crystal display device and method for generating the three primary colors and combinations thereof including black and white is disclosed using, at most, two adjacent discrete subpixels which together form a full color pixel. At least one dual STN cell system is included in each device, such controlled by EXCLUSIVE OR (XOR) logic.

Claims

1. A liquid crystal display device for generating three primary colors and combinations thereof including black and white, using at most two adjacent discrete subpixels which together form a full color pixel, comprising:

first, second and third optical assemblies which together define either one or at most two subpixels;

said optical assemblies together include at least three liquid crystal display cells and cooperating optical components, said three liquid crystal display cells each capable of being in a select state and a non-select state at different times, and said liquid crystal display cells and said cooperating optical components being arranged in a manner which provides binary combinations of selected states and non-selected states, so that at least one of each of said colors is generated by one of said binary combinations of select states and non-select states;

wherein at least one of said optical assemblies includes two liquid crystal display cells and their respective states are controlled by the logic of EXCLUSIVE OR (XOR) so that in either state in which both liquid crystal display cells are in the same state, a particular color will be blocked and in either state in which both liquid crystal display cells are in different states, said particular one of said colors will be transmitted therethrough.

2. A device as recited in claim 1 wherein said liquid crystal display cells are twisted nematic liquid crystal display (TN LCD) panels.

3. A device as recited in claim 2, wherein:

said cooperating components include polarizers;

said first optical assembly includes first and second liquid crystal display cells and a first entrance polarizer and a first exit polarizer;

said second optical assembly includes third and fourth liquid crystal display cells and a second entrance polarizer and a second exit polarizer; and

wherein said first exit polarizer and said second entrance polarizer are the same polarizer.

4. A device as recited in claim 2, wherein;

said first optical assembly includes a first liquid crystal display cell and a second liquid crystal display cell; and

said second optical assembly is adjacent to said first optical assembly, said second optical assembly including a third liquid crystal display cell and a retardation film; and

linear to said second optical assembly and adjacent to said first optical assembly, said third optical assembly including said fourth liquid crystal display cell and a retardation film.

5. A device as recited in claim 2, wherein;

said first optical assembly includes said first liquid crystal display cell and said second liquid crystal display cell; and

said second optical assembly is adjacent to said first optical assembly, and includes said third liquid crystal display cell and said fourth liquid crystal display cell; and

linear to said second optical assembly and adjacent to said first optical assembly, said third optical assembly includes said fourth liquid crystal display cell in a shared arrangement with said second optical assembly, and a retardation film.

6. A device as recited in claim 2, wherein;

said first optical assembly includes a first liquid crystal display cell and a second liquid crystal display cell;

linearly arranged with said first optical assembly, a second optical assembly including a third liquid crystal display cell and said fourth liquid crystal display cell; and

linearly arranged with said second optical assembly, a third optical assembly including said second liquid crystal display cell in a share arrangement with said first optical assembly and said third liquid crystal display cell in a shared arrangement with said second optical assembly.

7. A device as recited in claim 2, wherein:

said first optical assembly includes a first liquid crystal display cell and a second liquid crystal display cell;

linearly arranged with said first optical assembly, said second optical assembly including a third liquid crystal display cell and said fourth liquid crystal display cell; and

co-axially arranged with said second optical assembly, a third optical assembly includes said third liquid crystal display cell in a shared arrangement with said second optical assembly and a retardation film.

8. A device as recited in claim 2, further comprising:

an optional optical assembly, linearly aligned with said first, second and third optical assemblies, wherein said optional optical assembly includes said fourth liquid crystal display cell.

9. A device as recited in claim 1 wherein said liquid crystal display cells are supertwisted nematic liquid crystal display (STN LCD) panels.

10. A device as recited in claim 1 wherein said liquid crystal display cells are ferroelectric liquid crystal display panels.

11. A device as recited in claim 1, further comprising:

a fourth liquid crystal display cell capable of being in a select state and a non-select state at different times positioned within one of said optical assemblies; and

wherein said first, second, third and fourth liquid crystal display cells are arranged in a manner which provides binary combinations of select and non-select states, so that one of said colors is generated by at least one of said binary combinations.

12. A device as recited in claim 1 wherein two of said cells are individual cell pixels adjacent to one another on a common cell panel.

13. A device as recited in claim 1, wherein:

said cooperating components include polarizers;

said first optical assembly includes a first liquid crystal display cell and a first entrance polarizer and a first exit polarizer;

said second optical assembly includes a second and a third liquid crystal display cell and a second entrance polarizer and a second exit polarizer; and

wherein said first exit polarizer and said second entrance polarizer are the same polarizer.

14. A device as recited in claim 1, wherein said cooperating components include a plurality of polarizers;

and wherein at least one of said plurality of polarizers is shared by two optical assemblies.

15. A device as recited in claim 1 wherein said cooperating components include retardation films.

16. A device as recited in claim 1, wherein:

a first liquid crystal display cell and a second liquid crystal display cell are included in said first optical assembly; and

said second liquid crystal display cell and a third liquid crystal display cell are included in said second optical assembly.

17. A device as recited in claim 1, wherein:

said first optical assembly includes a first cell and a second liquid crystal display cell;

linearly arranged with said first optical assembly, said second optical assembly includes said second liquid crystal display cell in a shared arrangement with said first optical assembly; and

linearly arranged with said first and second optical assemblies, said third optical assembly includes, in a shared arrangement with said first and second optical assemblies, said second liquid crystal display cell and further includes a third liquid crystal display cell.

18. A device as recited in claim 1, wherein:

said first optical assembly includes a first liquid crystal display cell;

linearly arranged with said first optical assembly, said second optical assembly includes a second liquid crystal display cell and a third liquid crystal display cell; and

co-axially arranged with said second optical assembly said third optical assembly includes said second liquid crystal display cell in a shared arrangement with said second optical assembly and a first retardation film.

19. A device as recited in claim 1, wherein:

said first optical assembly includes a first liquid crystal display cell and a second liquid crystal display cell;

linearly and partially co-axially arranged with said first optical assembly, said second optical assembly includes said second liquid crystal display cell in a shared arrangement with said first optical assembly and a third liquid crystal display cell; and

linearly and co-axially arranged with said second optical assembly, said third optical assembly including said first, second and third liquid crystal display cells.

20. A liquid crystal display device including three optical assemblies, each for generating one of three primary colors so that the three primary color and combinations thereof including black and white are generated, using at most two adjacent discrete subpixels which together form a full color pixel, comprising:

a first liquid crystal display cell capable of being in a select state and a non-select state at different times;

a second liquid crystal display cell capable of being in a select state and a non-select state at different times;

a third liquid crystal display cell capable of being in a select state and a non-select state at different times;

wherein said liquid crystal display cells and cooperating optical components are arranged in a manner which provides binary combinations of selected states and non-selected states, so that at least one of each of said colors is generated by one of said binary combinations of select states and non-select states; and

wherein two of said liquid crystal display cells are included in an optical assembly such that their respective states are controlled by EXCLUSIVE OR (XOR) logic so that in either state in which both liquid crystal display cells are in the same state, a particular color will be blocked, and in either state in which both liquid crystal display cells are in different states, said particular one of said colors will be transmitted therethrough.

21. A device as recited in claim 20 wherein said cooperating optical components include an entrance polarizer and an exit polarizer for each of said optical assemblies.

22. A device as recited in claim 20 wherein said compensating optical components include retardation films.

23. A device as recited in claim 20 wherein said liquid crystal display cells are twisted nematic liquid crystal display (TN LCD) panels.

24. A device as recited in claim 20 wherein said liquid crystal display cells are supertwisted nematic liquid crystal display (STN LCD) panels.

25. A device as recited in claim 20 wherein said liquid crystal display cells are ferroelectric liquid crystal display panels.

26. A method for arranging optical components so that they generate three primary colors, the three complementary colors and black and white, comprising the steps of:

providing first, second and third optical assemblies, each for controlling a different primary color;

including in said optical assemblies a least three liquid crystal display cells and cooperating optical components, said three liquid crystal display cells each capable of being in a select state and a non-select state at different times;

arranging said first, second and third liquid crystal display cells in a manner which provides binary combinations of select states and non-select states so that each of said colors is generated by one of said binary combinations of select states and non-select state, and including in at least one of said optical assemblies, two liquid crystal display cells, so that their respective states are controlled by EXCLUSIVE OR (XOR) logic so that in either state in which both liquid crystal display cells are in the same state, a particular color will be blocked, ad in either state in which both liquid crystal display cells are in different states, said particular one of said colors will be transmitted therethrough.

27. A method as recited in claim 26 wherein said liquid crystal display cells are twisted nematic liquid crystal display (TN LCD) panels.

28. A method as recited in claim 26 wherein said liquid crystal display cells are supertwisted nematic liquid crystal display (STN LCD) panels.

29. A method as recited in claim 26 wherein said liquid crystal display cells are ferroelectric liquid crystal display panels.

30. A method as recited in claim 26 further comprising the steps of:

including in one of said optical assemblies a fourth liquid crystal display cell capable of being in a select state and a non-select state at different times; and

arranging said first, second, third and fourth liquid crystal display cells in a manner which provides binary combinations of select states and non-select states so that each of said colors is generated by at least one of said binary combinations of select states and non-select state.

31. A method recited in claim 30, further comprising the steps of:

positioning polarizers to cooperate with said liquid crystal display cells;

including in said first optical assembly, a first liquid crystal display cell, a first entrance polarizer and a first exit polarizer;

including in said second optical assembly, a second liquid crystal display cell, a third liquid crystal display cell, a second entrance polarizer and a second exit polarizer; and

positioning said first exit polarizer so that it also acts as said second entrance polarizer.

32. A method as recited in claim 30, further comprising the steps of:

positioning polarizers to cooperate with said liquid crystal display cells;

including in said first optical assembly, a first liquid crystal display cell, said second liquid crystal display cell, a first entrance polarizer and a first exit polarizer;

including in said second optical assembly, a third liquid crystal display cell, a said fourth liquid crystal display cell, a second entrance polarizer and a second exit polarizer; and

positioning said first exit polarizer so that it also acts as said second entrance polarizer.

33. A liquid crystal display device for generating three primary colors and combinations thereof including black and white, each of said primary colors generated by a different optical assembly, said device using at most two adjacent discrete subpixels which together form a full color pixel, comprising:

a first optical assembly for controlling a first primary color;

a second optical assembly, neighboring said first optical assembly, said second optical assembly for controlling a second primary color;

a third optical assembly, neighboring said second optical assembly, said third optical assembly for controlling a third primary color;

a first liquid crystal display cell capable of being in a select state and a non-select state at different times positioned within said first optical assembly;

a second liquid crystal display cell capable of being in a select state and a non-select state at different times positioned within one of said optical assemblies;

a third liquid crystal display cell capable of being in a select state and a non-select state at different times positioned within one of said optical assemblies;

wherein said first, second and third liquid crystal display cells are ordered in a manner which provides binary combinations of select states and non-select states so that each of said colors is generated by one of said binary combinations of select states and non-select states; and

wherein at least one of said optical assemblies includes two liquid crystal display cells and their respective states are controlled by EXCLUSIVE OR (XOR) logic so that in either state in which both liquid crystal display cells are in the same state, a particular color will be blocked, and in either state in which both liquid crystal display cells are in different states, said particular one of said colors will be transmitted therethrough.

34. A device as recited in claim 33 wherein said liquid crystal display cells are twisted nematic liquid crystal display (TN LCD) panels.

35. A device as recited in claim 33 wherein said liquid crystal display cells are supertwisted nematic liquid crystal display (STN LCD) panels.

36. A device as recited in claim 33 wherein said liquid crystal display cells are ferroelectric liquid crystal display panels.

37. A device as recited in claim 33 further comprising cooperating optical components, such including retardation films.

38. A device as recited in claim 33 further comprising cooperative optical components, such including an entrance polarizer and an exit polarizer for each of said optical assemblies.

39. A device as recited in claim 33 further comprising cooperative optical components, such including a backlighting system.

40. A device as recited in claim 33 further comprising cooperative optical components, such including a projection lens system.