COLOR FILTERING AND ABSORBING TOTAL INTERNAL REFLECTION IMAGE DISPLAY

• US 20020063963A1
• Filed: 11/30/2000
• Published: 05/30/2002
• Est. Priority Date: 11/30/2000
• Status: Active Grant

• Current Assignee: Concord HK International Education Limited
• Original Assignee: University of British Columbia
• Inventors: Whitehead, Lorne A., Mossman, Michele Ann
• Granted Patent: US 6,384,979 B1
• Time in Patent Office: Days
• US Class Current: 359/619
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/1677 Structural association of cells with optical devices, e.g. reflectors or illuminating devices
• CPC Class Codes: G02F 1/195 by using frustrated reflection digital reflection using controlled total internal reflection G02F1/315
• CPC Class Codes: G02F 2203/026 attenuated or frustrated internal reflection

Abstract

A color image display having a spatially uniform distribution of at least two different “types” of prism structure. The first type consists of a prism, a color filter associated with one of the prism'"'"'s facets and two color absorbing control members, each of which can be biased away from or into optical contact with one of the prism'"'"'s other two facets. The color filter has a first spectral absorption characteristic, and the control members have second and third spectral absorption characteristics respectively. The second type of prism structure consists of a second prism, a color filter associated with one of the second prism'"'"'s facets and at least one color absorbing control member which can be biased away from or into optical contact with one of the second prism'"'"'s other two facets. The second prism'"'"'s color filter and control member have fourth and fifth spectral absorption characteristics respectively. The spectral absorption characteristics are selected such that, for any selected set comprising proximate ones of each of the two types of prism structure, controlled movement of the members between particular selected combinations of their possible respective positions causes the set as a whole to reflect light which has an average spectral reflectance characteristic corresponding to any one of three independent colors, with no one of the independent colors being obtainable by mixing any other two of the independent colors.

Claims

1. Color display apparatus comprising a spatially uniform distribution of at least first and second types of prism structure, wherein:

(a) said first type of prism structure further comprises;

(i) a first prism;

(ii) a first color filter positioned to filter light incident upon a first facet of said first prism, said first color filter having a first selected spectral absorption characteristic;

(iii) a first member having a second selected spectral absorption characteristic, said first member movable with respect to a second facet of said first prism between;

(1) a first position in which said first member is in optical contact with said second facet, producing a first absorptive state in which total internal reflection of light rays at said second facet is reduced as a function of wavelength in accordance with said second selected spectral absorption characteristic;

(2) a second position in which said first member is not in optical contact with said second facet, producing a first reflective state in which light incident upon said second facet is totally internally reflected toward a third facet of said first prism;

(iv) a second member having a third selected spectral absorption characteristic, said first member movable with respect to said third facet of said first prism between;

(1) a third position in which said second member is in optical contact with said third facet, producing a second absorptive state in which total internal reflection of light rays at said third facet is reduced as a function of wavelength in accordance with said third selected spectral absorption characteristic;

(2) a fourth position in which said second member is not in optical contact with said third facet, producing a second reflective state in which light incident upon said third facet is totally internally reflected toward and through said first color filter;

(b) said second type of prism structure further comprises;

(i) a second prism;

(ii) a second color filter positioned to filter light incident upon a first facet of said second prism, said second color filter having a fourth selected spectral absorption characteristic;

(iii) a third member having a fifth selected spectral absorption characteristic, said third member movable with respect to a second facet of said second prism between;

(1) a fifth position in which said third member is in optical contact with said second facet of said second prism, producing a third absorptive state in which total internal reflection of light rays at said second facet of said second prism is reduced as a function of wavelength in accordance with said fifth selected spectral absorption characteristic;

(2) a sixth position in which said third member is not in optical contact with said second facet of said second prism, producing a third reflective state in which light incident upon said second facet of said second prism is totally internally reflected at said second facet of said second prism;

(c) said spectral absorption characteristics are selected such that, for any selected set comprising proximate ones of all of said types of prism structure, controlled movement of said members between particular selected combinations of said respective positions causes said set to reflect light having an average spectral reflectance characteristic corresponding to any one of three independent colors; and

,

(d) no one of said independent colors is obtainable by mixing any other two of said independent colors.

2. Color display apparatus as defined in claim 1, wherein:

(a) each one of said first types of prism structure is longitudinally adjacent to one of said second types of prism structure; and

,

(b) each one of said second types of prism structure is longitudinally adjacent to one of said first types of prism structure.

3. Color display apparatus as defined in claim 1, wherein:

(a) said second type of prism structure further comprises;

(i) a fourth member having a sixth selected spectral absorption characteristic, said fourth member movable with respect to a third facet of said second prism between;

(1) a seventh position in which said fourth member is in optical contact with said third facet of said second prism, producing a fourth absorptive state in which total internal reflection of light rays at said third facet of said second prism is reduced as a function of wavelength in accordance with said sixth selected spectral absorption characteristic;

(2) an eighth position in which said fourth member is not in optical contact with said third facet of said second prism, producing a fourth reflective state in which light incident upon said third facet of said second prism is totally internally reflected toward and through said second color filter;

(b) said spatially uniform distribution further comprises a third type of prism structure, said third type of prism structure further comprising;

(i) a third prism;

(ii) a third color filter positioned to filter light incident upon a first facet of said third prism, said third color filter having a seventh selected spectral absorption characteristic;

(iii) a fifth member having an eighth selected spectral absorption characteristic, said fifth member movable with respect to a second facet of said third prism between;

(1) a ninth position in which said fifth member is in optical contact with said second facet of said third prism, producing a fifth absorptive state in which total internal reflection of light rays at said second facet of said third prism is reduced as a function of wavelength in accordance with said eighth selected spectral absorption characteristic;

(2) a tenth position in which said fifth member is not in optical contact with said second facet of said third prism, producing a fifth reflective state in which light incident upon said second facet of said third prism is totally internally reflected toward a third facet of said third prism;

(iv) a sixth member having a ninth selected spectral absorption characteristic, said sixth member movable with respect to a third facet of said third prism between;

(1) an eleventh position in which said sixth member is in optical contact with said third facet of said third prism, producing a sixth absorptive state in which total internal reflection of light rays at said third facet of said third prism is reduced as a function of wavelength in accordance with said ninth selected spectral absorption characteristic; and

,

(2) a twelfth position in which said sixth member is not in optical contact with said third facet of said third prism, producing a sixth reflective state in which light incident upon said third facet of said third prism is totally internally reflected toward and through said third color filter.

4. Color display apparatus as defined in claim 3, wherein said first spectral characteristic further comprises a first primary color, said fourth spectral characteristic further comprises a second primary color, and said seventh spectral characteristic further comprises a third primary color.

5. Color display apparatus as defined in claim 4, wherein said first, second and third primary colors are subtractive primary colors.

6. Color display apparatus as defined in claim 4, wherein said second spectral characteristic further comprises said second primary color, said third spectral characteristic further comprises said third primary color, said fifth spectral characteristic further comprises said third primary color, said sixth spectral characteristic further comprises said first primary color, said eighth spectral characteristic further comprises said first primary color, and said ninth spectral characteristic further comprises said second primary color.

7. Color display apparatus as defined in claim 1, wherein:

(a) said first member further comprises a first plurality of absorptive particles suspended in an electrophoretic medium contacting said second facet of said first prism;

(b) said second member further comprises a second plurality of absorptive particles suspended in an electrophoretic medium contacting said third facet of said first prism; and

,

(c) said third member further comprises a third plurality of absorptive particles suspended in an electrophoretic medium contacting said second facet of said second prism.

8. Color display apparatus as defined in claim 3, wherein:

(a) said first member further comprises a first plurality of absorptive particles suspended in an electrophoretic medium contacting said second facet of said first prism;

(b) said second member further comprises a second plurality of absorptive particles suspended in an electrophoretic medium contacting said third facet of said first prism;

(c) said third member further comprises a third plurality of absorptive particles suspended in an electrophoretic medium contacting said second facet of said second prism;

(d) said fourth member further comprises a fourth plurality of absorptive particles suspended in an electrophoretic medium contacting said third facet of said second prism;

(e) said fifth member further comprises a fifth plurality of absorptive particles suspended in an electrophoretic medium contacting said second facet of said third prism; and

,

(f) said sixth member further comprises a sixth plurality of absorptive particles suspended in an electrophoretic medium contacting said third facet of said third prism.

9. Color display apparatus as defined in claim 3, wherein:

(a) said first member and said sixth member of another one of said third type of prism structure adjacent to said first type of prism structure together comprise a first plurality of absorptive particles suspended in an electrophoretic medium contacting said second facet of said first prism;

(b) said second member and said third member together comprise a second plurality of absorptive particles suspended in an electrophoretic medium contacting said third facet of said first prism and contacting said second facet of said second prism; and

,

(c) said fourth member and said fifth member together comprise a third plurality of absorptive particles suspended in an electrophoretic medium contacting said third facet of said second prism and contacting said second facet of said third prism.

10. Color display apparatus as defined in claim 1, wherein said first, second and third members each further comprise a deformable elastomeric member.

11. Color display apparatus as defined in claim 3, wherein said first, second, third, fourth, fifth and sixth members each further comprise a deformable elastomeric member.

12. Color display apparatus as defined in claim 11, wherein said second member and said third member together comprise one of said deformable elastomeric members and fourth member and said fifth member together comprise another one of said deformable elastomeric members.

13. Color display apparatus as defined in claim 1, wherein said first facets of said first and second prisms collectively comprise a viewing surface, said apparatus further comprising:

(a) a substrate extending substantially parallel to said viewing surface;

(b) a first electrode on said second and third facets of each of said first and second prisms;

(c) a second electrode on said substrate adjacent said second facet of said first prism;

(d) a third electrode on said substrate adjacent said third facet of said first prism;

(e) a fourth electrode on said substrate adjacent said second facet of said second prism;

said apparatus further comprising a voltage source for selectably applying;

(i) a first voltage potential between said first and second electrodes to move said first member into said first position;

(ii) a second voltage potential between said first and second electrodes to move said first member into said second position;

(iii) a third voltage potential between said first and third electrodes to move said second member into said third position;

(iv) a fourth voltage potential between said first and third electrodes to move said second member into said fourth position;

(v) a fifth voltage potential between said first and fourth electrodes to move said third member into said fifth position; and

,

(vi) a sixth voltage potential between said first and fourth electrodes to move said third member into said sixth position.

14. Color display apparatus as defined in claim 3, wherein said first facets of said first, second and third prisms collectively comprise a viewing surface, said apparatus further comprising:

(a) a substrate extending substantially parallel to said viewing surface;

(b) a first electrode on said second and third facets of each of said first, second and third prisms;

(c) a second electrode on said substrate adjacent said second facet of said first prism;

(d) a third electrode on said substrate adjacent said third facet of said first prism;

(e) a fourth electrode on said substrate adjacent said second facet of said second prism;

(f) a fifth electrode on said substrate adjacent said third facet of said second prism;

(g) a sixth electrode on said substrate adjacent said second facet of said third prism;

(h) a seventh electrode on said substrate adjacent said third facet of said third prism;

said apparatus further comprising a voltage source for selectably applying;

(i) a first voltage potential between said first and second electrodes to move said first member into said first position;

(ii) a second voltage potential between said first and second electrodes to move said first member into said second position;

(iii) a third voltage potential between said first and third electrodes to move said second member into said third position;

(iv) a fourth voltage potential between said first and third electrodes to move said second member into said fourth position;

(v) a fifth voltage potential between said first and fourth electrodes to move said third member into said fifth position;

(vi) a sixth voltage potential between said first and fourth electrodes to move said third member into said sixth position;

(vii) a seventh voltage potential between said first and fifth electrodes to move said fourth member into said seventh position;

(viii) an eighth voltage potential between said first and sixth electrodes to move said fifth member into said ninth position; and

,

(ix) a tenth voltage potential between said first and seventh electrodes to move said sixth member into said eleventh position.

15. Color display apparatus as defined in claim 1, wherein said color filters are formed on said first facets of said respective prisms.

16. Color display apparatus as defined in claim 1, wherein said color filters are formed within said first facets of said respective prisms.

17. Color display apparatus as defined in claim 3, wherein said color filters are formed on said first facets of said respective prisms.

18. Color display apparatus as defined in claim 3, wherein said color filters are formed within said first facets of said respective prisms.

19. Color display apparatus as defined in claim 7, wherein said electrophoretic medium is Fluorinert.

20. Color display apparatus as defined in claim 8, wherein said electrophoretic medium is Fluorinert.

21. Color display apparatus as defined in claim 1, wherein said prisms are formed of zinc sulphide.

22. Color display apparatus as defined in claim 3, wherein said prisms are formed of zinc sulphide.

23. Color display apparatus as defined in claim 10, wherein said elastomer members have stiff surfaces.

24. Color display apparatus as defined in claim 11, wherein said elastomer members have stiff surfaces.

25. Color display apparatus as defined in claim 7, wherein:

(a) said first plurality of absorptive particles suspended in said electrophoretic medium are confined within a first channel formed adjacent said second facet of said first prism;

(b) said second plurality of absorptive particles suspended in said electrophoretic medium are confined within a second channel formed adjacent said third facet of said first prism; and

,

(c) said third plurality of absorptive particles suspended in said electrophoretic medium are confined within a third channel formed adjacent said second facet of said second prism.

26. Color display apparatus as defined in claim 8, wherein:

(a) said first and said sixth plurality of absorptive particles suspended in said electrophoretic medium are confined together within a first channel formed adjacent said second facet of said first prism and adjacent said third facet of said third prism of another one of said third type of prism structure adjacent to said first type of prism structure;

(b) said second and said third plurality of absorptive particles suspended in said electrophoretic medium are confined together within a second channel formed adjacent said third facet of said first prism and adjacent said second facet of said second prism; and

,

(c) said fourth and said fifth plurality of absorptive particles suspended in said electrophoretic medium are confined together within a third channel formed adjacent said second facet of said third prism and adjacent said second facet of said third prism.

27. Color display apparatus as defined in claim 7, wherein:

(a) said first plurality of absorptive particles suspended in said electrophoretic medium are distributed among and confined within a first plurality of compartments formed along and adjacent said second facet of said first prism;

(b) said second plurality of absorptive particles suspended in said electrophoretic medium are distributed among and confined within a second plurality of compartments formed along and adjacent said third facet of said first prism; and

,

(c) said third plurality of absorptive particles suspended in said electrophoretic medium are distributed among and confined within a third plurality of compartments formed along and adjacent said second facet of said second prism.

28. Color display apparatus as defined in claim 8, wherein:

(a) said first and sixth plurality of absorptive particles suspended in said electrophoretic medium are distributed among and confined together within a first plurality of compartments formed along and adjacent said second facet of said first prism and adjacent said third facet of said third prism of another one of said third type of prism structure adjacent to said first type of prism structure;

(b) said second and third plurality of absorptive particles suspended in said electrophoretic medium are distributed among and confined together within a second plurality of compartments formed along and adjacent said third facet of said first prism and along and adjacent said second facet of said second prism; and

,

(c) said fourth and fifth plurality of absorptive particles suspended in said electrophoretic medium are distributed among and confined together within a third plurality of compartments formed along and adjacent said second facet of said third prism and along and adjacent said second facet of said third prism.

30. A method as defined in claim 29, wherein:

(a) said fifth selected spectral component of said fourth light ray is selectably absorbed at said second facet of said second prism and totally internally reflecting toward said third facet of said second prism as said fifth light ray;

(b) said spatially uniform distributed locations further comprising a third type of location;

said method further comprising;

(i) selectably absorbing a sixth selected spectral component of said fifth light ray at said third facet of said second prism and totally internally reflecting toward and through said first facet of said second prism a sixth light ray lacking said fourth spectral component and selectably lacking said fifth spectral component and selectably lacking said sixth spectral component;

(c) at each one of said third type of said locations;

(i) filtering said incident light through a first facet of a third prism to absorb a seventh selected spectral component of said incident light and reflect toward a second facet of said third prism a seventh light ray lacking said seventh spectral component;

(ii) selectably absorbing an eighth selected spectral component of said seventh light ray at said second facet of said third prism and totally internally reflecting toward a third facet of said third prism an eighth light ray lacking said seventh spectral component and selectably lacking said eighth spectral component; and

,

(iii) selectably absorbing a ninth selected spectral component of said eighth light ray at said third facet of said third prism and totally internally reflecting toward and through said first facet of said third prism a ninth light ray lacking said seventh spectral component and selectably lacking said eighth spectral component and selectably lacking said ninth spectral component.

31. A method as defined in claim 30, wherein said first spectral component further comprises a first primary color, said fourth spectral component further comprises a second primary color, and said seventh spectral component further comprises a third primary color.

32. A method as defined in claim 31, wherein said first, second and third primary colors are subtractive primary colors.

33. A method as defined in claim 32, wherein said second spectral component further comprises said second primary color, said third spectral component further comprises said third primary color, said fifth spectral component further comprises said third primary color, said sixth spectral component further comprises said first primary color, said eighth spectral component further comprises said first primary color, and said ninth spectral component further comprises said second primary color.

34. A method as defined in claim 29, wherein:

(a) said selectably absorbing said second selected spectral component further comprises electrophoretically moving a first plurality of absorptive particles into optical contact with said second facet of said first prism;

(b) said selectably absorbing said third selected spectral component further comprises electrophoretically moving a second plurality of absorptive particles into optical contact with said third facet of said first prism; and

,

(c) said selectably absorbing said fifth selected spectral component further comprises electrophoretically moving a third plurality of absorptive particles into optical contact with said second facet of said second prism.

35. A method as defined in claim 30, wherein:

(a) said selectably absorbing said second selected spectral component further comprises electrophoretically moving a first plurality of absorptive particles into optical contact with said second facet of said first prism;

(b) said selectably absorbing said third selected spectral component further comprises electrophoretically moving a second plurality of absorptive particles into optical contact with said third facet of said first prism;

(c) said selectably absorbing said fifth selected spectral component further comprises electrophoretically moving a third plurality of absorptive particles into optical contact with said second facet of said second prism;

(d) said selectably absorbing said sixth selected spectral component further comprises electrophoretically moving a fourth plurality of absorptive particles into optical contact with said second facet of said second prism;

(e) said selectably absorbing said eighth selected spectral component further comprises electrophoretically moving a fifth plurality of absorptive particles into optical contact with said second facet of said third prism; and

,

(f) said selectably absorbing said ninth selected spectral component further comprises electrophoretically moving a sixth plurality of absorptive particles into optical contact with said second facet of said third prism.

36. A method as defined in claim 29, wherein:

(a) said selectably absorbing said second selected spectral component further comprises moving a first elastomeric member into optical contact with said second facet of said first prism;

(b) said selectably absorbing said third selected spectral component further comprises moving a second elastomeric member into optical contact with said third facet of said first prism; and

,

(c) said selectably absorbing said fifth selected spectral component further comprises moving a third elastomeric member into optical contact with said second facet of said second prism.

37. A method as defined in claim 30, wherein:

(a) said selectably absorbing said second selected spectral component further comprises moving a first elastomeric member into optical contact with said second facet of said first prism;

(b) said selectably absorbing said third selected spectral component further comprises moving a second elastomeric member into optical contact with said third facet of said first prism;

(c) said selectably absorbing said fifth selected spectral component further comprises moving a third elastomeric member into optical contact with said second facet of said second prism;

(d) said selectably absorbing said sixth selected spectral component further comprises moving a fourth elastomeric member into optical contact with said second facet of said second prism;

(e) said selectably absorbing said eighth selected spectral component further comprises moving a fifth elastomeric member into optical contact with said second facet of said second prism; and

,

(f) said selectably absorbing said ninth selected spectral component further comprises moving a sixth elastomeric member into optical contact with said second facet of said third prism.

38. A method as defined in claim 34, further comprising:

(a) forming a first channel adjacent said second facet of said first prism, placing an electrophoretic medium in said first channel, and suspending said first plurality of absorptive particles in said electrophoretic medium within said first channel;

(b) forming a second channel adjacent said third facet of said first prism, placing an electrophoretic medium in said second channel, and suspending said second plurality of absorptive particles in said electrophoretic medium within said second channel; and

,

(c) forming a third channel adjacent said second facet of said second prism, placing an electrophoretic medium in said third channel, and suspending said third plurality of absorptive particles in said electrophoretic medium within said third channel.

39. A method as defined in claim 35, further comprising:

(a) forming a first channel adjacent said second facet of said first prism and adjacent said third facet of said third prism, placing an electrophoretic medium in said first channel, and suspending said first and sixth plurality of absorptive particles together in said electrophoretic medium within said first channel;

(b) forming a second channel adjacent said third facet of said first prism and adjacent said second facet of said second prism, placing an electrophoretic medium in said second channel, and suspending said second and said third plurality of absorptive particles together in said electrophoretic medium within said second channel; and

,

(c) forming a third channel adjacent said third facet of said second prism and adjacent said second facet of said third prism, placing an electrophoretic medium in said third channel, and suspending said fourth and said fifth plurality of absorptive particles together in said electrophoretic medium within said third channel.

40. A method as defined in claim 34, further comprising:

(a) forming a first plurality of compartments along and adjacent said second facet of said first prism, placing an electrophoretic medium in each of said first plurality of compartments, and suspending said first plurality of absorptive particles in said electrophoretic medium within each of said first plurality of compartments;

(b) forming a second plurality of compartments along and adjacent said third facet of said second prism, placing an electrophoretic medium in each of said second plurality of compartments, and suspending said second plurality of absorptive particles in said electrophoretic medium within each of said second plurality of compartments; and

,

(c) forming a third plurality of compartments along and adjacent said second facet of said second prism, placing an electrophoretic medium in each of said third plurality of compartments, and suspending said third plurality of absorptive particles in said electrophoretic medium within each of said third plurality of compartments.

41. A method as defined in claim 35, further comprising:

(a) forming a first plurality of compartments along and adjacent said second facet of said first prism and along and adjacent said third facet of said third prism, placing an electrophoretic medium in each of said first plurality of compartments, and suspending said first and sixth plurality of absorptive particles together in said electrophoretic medium within each of said first plurality of compartments;

(b) forming a second plurality of compartments along and adjacent said third facet of said second prism and along and adjacent said second facet of said second prism, placing an electrophoretic medium in each of said second plurality of compartments, and suspending said second and third plurality of absorptive particles together in said electrophoretic medium within each of said second plurality of compartments; and

,

(c) forming a third plurality of compartments along and adjacent said third facet of said second prism and along and adjacent said second facet of said third prism, placing an electrophoretic medium in each of said third plurality of compartments, and suspending said fourth and fifth plurality of absorptive particles together in said electrophoretic medium within each of said third plurality of compartments.

29. A color image display method, comprising filtering and totally internally reflecting light at each one of a plurality of at least first and second types of spatially uniform distributed locations, said method further comprising:

(a) at each one of said first type of said locations;

(i) filtering incident light through a first facet of a first prism to absorb a first selected spectral component of said incident light and reflect toward a second facet of said first prism a first light ray lacking said first spectral component;

(ii) selectably absorbing a second selected spectral component of said first light ray at said second facet of said first prism and totally internally reflecting toward a third facet of said first prism a second light ray lacking said first spectral component and selectably lacking said second spectral component;

(iii) selectably absorbing a third selected spectral component of said second light ray at said third facet of said first prism and totally internally reflecting toward and through said first facet of said first prism a third light ray lacking said first spectral component and selectably lacking said second spectral component and selectably lacking said third spectral component;

(b) at each one of said second type of said locations;

(i) filtering said incident light through a first facet of a second prism to absorb a fourth selected spectral component of said incident light and reflect toward a second facet of said second prism a fourth light ray lacking said fourth spectral component;

(ii) selectably absorbing a fifth selected spectral component of said fourth light ray at either one or both of;

(1) said second facet of said second prism;

(2) a third facet of said second prism;

to produce a fifth light ray lacking said fourth spectral component and selectably lacking said fifth spectral component;

(iii) at said second facet of said second prism, totally internally reflecting said either one of said fourth or fifth light rays toward said third facet of said second prism;

(iv) at said third facet of said second prism, totally internally reflecting said fifth light ray toward and through said first facet of said second prism;

wherein;

(v) said spectral components are selected such that, for any selected set comprising proximate ones of all of said types of locations, particular selected combinations of said selectably absorbing of said spectral components causes said set to reflect light having an average spectral reflectance characteristic corresponding to any one of three independent colors; and

,

(vi) no one of said independent colors is obtainable by mixing any other two of said independent colors.