Intra-pixel illumination system
View Patent ↗Methods and systems are disclosed to provide intra-pixel illumination to a modulating display panel, where regions of a pixel are provided incident light with controlled intensity and color at different periods of the panel's addressing cycle. This can lead to increased resolution beyond that intrinsic to the panel's physical make up, providing an enhanced resolution 2D panel, as well as a high resolution panel suitable for autostereoscopic purposes when used with a further lens array. For example, when the left hand side of all pixels are illuminated in one frame creating an image, and the right hand side of the pixels are illuminated within a second frame creating a further image, then the combined image, assuming temporal averaging, is twice the native resolution. Despite the temporal trade off, the eye's tolerance to local variation of color and intensity makes this feasible with realistic addressing periods.
1. A method for high resolution display presentation using intra-pixel illumination, the method comprising:
at a first point in time, illuminating a plurality of first subpixel regions on a liquid crystal display (LCD) modulating panel to present a first image frame on the LCD, each of the first subpixel regions comprising a plurality of first subpixels; and
at a second point in time, illuminating a plurality of second subpixel regions on the LCD to present a second image frame on the LCD, each of the second subpixel regions comprising a plurality of second subpixels,
wherein each of the first and second subpixels comprise a substantially nonoverlapping region within an LCD pixel,
wherein the first and second subpixel regions comprise substantially nonoverlapping areas of LCD pixels, and
wherein the illuminating of the plurality of first subpixel regions comprises temporally switching colored light between at least a first color and a second color provided to the first subpixel regions.
2. The method of claim 1 , wherein a subpixel is less than the size of any one individual modulating pixel of a liquid crystal display panel.
3. The method of claim 1 , wherein a subpixel is substantially half of the size of any one individual modulating pixel of a liquid crystal display panel.
4. The method of claim 1 , wherein the first subpixel region comprises a plurality of subpixels arranged vertically in a column of pixels on the LCD and substantially occupying the left half of the column of pixels, wherein the second subpixel region comprises a plurality of subpixels arranged vertically in the column of pixels on the LCD and substantially occupying the right half of the column of pixels.
5. The method of claim 1 , further comprising:
at a third point in time, illuminating a plurality of third subpixel regions on the LCD modulating panel; and
wherein the first, second, and third subpixel regions comprise substantially nonoverlapping areas of LCD pixels.
6. The method of claim 1 , further comprising:
activating a first set of light sources at the first point in time;
optically replicating light from the first set of light sources; and
projecting the optically replicated light toward the plurality of first subpixel regions.
7. The method of claim 6 , further comprising:
activating a second set of light sources at the second point in time;
optically replicating light from the second set of light sources; and
projecting the optically replicated light toward the plurality of second subpixel regions.
8. The method of claim 6 , wherein the first and second set of light sources comprise red, green, and blue light emitting diodes.
9. The method of claim 1 , wherein each subpixel region is illuminated with one of red, blue, or green colored light, wherein the subpixel illumination temporally cycles between the red, blue, and green colored light in each subpixel region to provide a uniform white spatially-averaged illumination to the LCD.
10. The method of claim 1 , further comprising scrolling through a plurality of scrolling stripe regions to hide display transition periods.
11. The method of claim 10 , further comprising selectively illuminating the scrolling stripe regions to provide scrolling illumination on the LCD panel synchronized with addressing of the LCD panel modulation.
12. The method according to claim 1 , further comprising providing red, green, and blue light in angularly separated color beams to a cylindrical lens array operable to direct the light toward one of the first and second subpixel regions.
13. The method of claim 1 , wherein illumination of the first subpixel regions illuminates a first image destined for a left eye, and wherein illumination of the second subpixel regions illuminates a second image destined for a right eye.
14. The method of claim 13 , further comprising directing light from the first subpixel region to the left eye and directing light from the second region to the right eye with a lenticular array located in the light path after the LCD modulating panel.
15. A method for illuminating a liquid crystal display (LCD) panel, the method comprising:
providing the LCD panel, wherein a pixel in the LCD panel comprises a left subpixel and a right subpixel, and wherein a first set of subpixels substantially comprise left subpixels,
wherein the second set of subpixels substantially comprise right subpixels, and wherein each of the left and right subpixels comprise a substantially nonoverlapping region within the pixel in the LCD panel;
illuminating the left subpixels in a first scrolling stripe region to present a first image destined for a left eye on the LCD;
illuminating the left subpixels in a second scrolling stripe region;
illuminating the right subpixels in the first scrolling stripe region to present a second image destined for a right eye on the LCD; and
illuminating the right subpixels in the second scrolling stripe region.
16. The method of claim 15 , wherein the light illuminating the first set of subpixels comprises light originating from a first set of light emitting diodes, and wherein the light illuminating the second set of subpixels comprises light originating from a second set of light emitting diodes.
17. The method of claim 15 , wherein the first set of subpixels in the first scrolling stripe region is illuminated in a first time phase, and wherein the first set of subpixels in the second scrolling stripe region is illuminated in a second time phase.
18. The method of claim 16 , wherein the second time phase follows the first time phase in time.
19. The method of claim 16 , wherein the second time phase at least partially overlaps the first time phase in time.
20. The method of claim 15 , further comprising:
illuminating the left subpixels in a third scrolling stripe region; and
illuminating the right subpixels in the third scrolling stripe region.
21. The method of claim 15 , wherein the first and second scrolling stripe regions are illuminated at different periods of the LCD panel's addressing cycle.
22. The method of claim 15 , further comprising:
generating first light from a first set of LEDs and directing the first light toward the left subpixels on the LCD panel; and
generating second light from a second set of LEDs and directing the second light toward the right subpixels on the LCD panel,
wherein light incident on each subpixel is one of red, green, and blue light.
23. The method according to claim 22 , further comprising providing the red, green, and blue light in angularly separated color beams to a cylindrical lens array operable to direct the first light toward the left subpixels on the LCD panel, and further operable to direct the second light toward the right subpixels on the LCD panel.
24. The method of claim 15 , wherein selective illumination of the scrolling stripe regions provide scrolling illumination on the LCD panel synchronized with addressing of the LCD panel modulation.
25. The method of claim 15 , wherein the scrolling stripe regions are created by temporally illuminating a lenticular sheet with light beams from one of a first and a second set of LEDs, the colored light beams having distinct incident angles.
26. The method of claim 15 , wherein illumination of the first set of subpixels illuminates a first image destined for a left eye, and wherein illumination of the second set of subpixels illuminates a second image destined for a right eye.
27. The method of claim 15 , wherein light is imaged on a diffuser prior to the LCD panel.
28. A direct view visual display comprising:
a liquid crystal (LC) modulating panel;
a temporally modulated illumination source engine operable to generate first light and second light;
a micro-optical array subsystem adjacent the LC modulating panel, and operable to direct the first light from the illumination source engine to a plurality of first subpixel regions on the LC modulating panel to present a first image frame on the LC modulating panel,
each of the first subpixel regions comprising a plurality of first subpixels, and operable to direct the second light from the illumination source engine to a plurality of second subpixel regions on the LC modulating panel to present a second image frame on the LC modulating panel,
each of the second subpixel regions comprising a plurality of second subpixels,
wherein each of the first and second subpixels comprise a substantially nonoverlapping region within an LC modulating panel pixel,
wherein the first and second subpixel regions comprise substantially nonoverlapping areas of LCD pixels, and
wherein the directing of the first light from the illumination source engine to the plurality of first subpixel regions comprises temporally switching the first light between at least a first color and a second color.
29. The direct view visual display of claim 28 , further comprising a cylindrical lens array operable to direct the first light toward the first subpixel regions on the LC modulating panel, and further operable to direct the second light toward the second subpixel regions on the LC modulating panel.
30. The direct view visual display of claim 28 , further comprising a controller operable to drive the illumination source engine to provide the first light and the second light.