3D projection system using laser light sources

• US 10,359,639 B2
• Filed: 06/01/2017
• Issued: 07/23/2019
• Est. Priority Date: 03/14/2011
• Status: Active Grant

• Current Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Original Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Inventors: Richards, Martin J.
• Primary Examiner(s): Tallman, Robert E.
• Application Number:
  US15/611,696
• Publication Number:
  US 20170336645A1
• Time in Patent Office: 782 Days
• Field of Search: 351 41, 3511596, 35115962, 35115963, 35115965, 35115966, 348 42, 348 58, 348 60, 359462, 359464, 359465, 359466
• CPC Class Codes: G02B 30/23 using wavelength separation, e.g. using anaglyph techniques
• CPC Class Codes: G02B 30/34 Stereoscopes providing a stereoscopic pair of separated images corresponding to parallactically displaced views of the same object, e.g. 3D slide viewers
• CPC Class Codes: H04N 13/324 Colour aspects
• CPC Class Codes: H04N 13/334 using spectral multiplexing
• CPC Class Codes: H04N 13/363 using image projection screens volumetric display H04N13/388

Abstract

Laser or narrow band light sources (e.g., red, green, and blue) are utilized to form left (e.g., R1, G1, B1) and right (e.g., R2, G2, B2) images of a 3D projection. Off-axis viewing of the projections which has the potential to cause crosstalk and/or loss of energy/brightness in any channel or color, is eliminated (or reduced to only highly oblique viewing angles) via the combined use of any of guard bands between light bands of adjacent channels, curvature of viewing filters, and selection of passband wavelengths that maximize usability of the passband as it “shifts” due to varying or increasing angles of off-axis viewing. Implemented with any number of light sources, the light sources selected may also be converted to showing 2D images where the additional light sources are utilized to affect a desirable increase in color gamut.

Claims

1. A laser display system configured to display 3D images comprising right and left images composed of spectrally separated laser lights, the laser display system comprising:

an image rendering device; and

3D viewing glasses comprising a left eye filter and a right eye filter, the left eye filter configured to transmit a set of at least one projected narrowband wavelength corresponding to a left view of a 3D image rendered by the image rendering device, the right eye filter configured to transmit a set of at least one projected narrowband wavelength corresponding to a right view of the 3D image rendered by the image rendering device, the filters configured to pass their corresponding set of at least one projected narrowband wavelength to a viewer when viewed through the glasses at normal angles and when viewed through the glasses at off-normal angles;

wherein the sets of projected narrowband wavelengths are all transmitted at first positions relative to the spectral properties of their corresponding filters when viewed normally and, when viewed at increasingly off-normal angles, at least one of each of the sets of projected narrowband wavelengths are transmitted at positions that are increasingly further from the first positions and increasingly closer to long wavelength ends of pass areas of the filters including areas of the filter that do not transmit any of the projected narrowband wavelengths when viewed normally; and

the projected narrowband wavelengths are laser wavelengths; and

wherein pass areas of the filters are constructed so that, when viewed normally, the projected narrowband wavelengths are transmitted at a shortest wavelength position of the passband that also provides a predetermined amount of transmission of the light through the passband.

2. The laser display system according to claim 1, wherein the filters comprise a tolerance pass area provided between a shortest of any narrowband wavelengths passed through a pass area of the filter when normally incident and a short wavelength end of the pass area.

3. The laser display system according to claim 2, wherein the filters comprise multiple tolerance pass areas each in different areas of the filter comprising a first tolerance pass area of a filter and a second tolerance pass area of the other filter, and wherein a bandwidth of the first tolerance pass area is different from a bandwidth of the second tolerance pass area.

4. The laser display system according to claim 2, wherein tolerance pass areas of one filter are larger than tolerance pass areas of the other filter.

5. The laser display system according to claim 2, wherein tolerance pass areas of a filter have different bandwidths.

6. The laser display system according to claim 1, wherein pass areas of the filters entirely surround all image carrying wavelengths of the images and pass wavelengths adjacent to the image carrying wavelengths when the wavelengths pass normally though the filters.

7. The laser display system according to claim 1, wherein pass areas of the filters entirely encompass all image carrying wavelengths of the images and wavelengths adjacent to image carrying wavelengths when the wavelengths are normally incident to the filters.

8. The laser display system according to claim 1, wherein pass areas of the filters entirely encompass all image carrying wavelengths of the laser display system and sets of non-image carrying wavelengths each set of non-image carrying wavelengths adjacent to at least one image carrying wavelength and a cut-off wavelength of a pass area of the filter.

9. The laser display system according to claim 1, wherein each pass area of the filters includes a shifting area that does not pass any image carrying wavelengths when the image carrying wavelengths are normally incident to the glasses.

10. The laser display system according to claim 1, wherein each pass area of the filters includes a shifting area that does not pass any image carrying wavelengths when the image carrying wavelengths are normally incident to the glasses, and, when incident at increasingly off-normal angles, a correspondingly increasing amount of the shifting area is utilized to pass image carrying wavelengths.

11. The laser display system according to claim 10, wherein the shifting areas of a filter comprise pass areas between a longest wavelength of a contiguous set of image carrying wavelengths and a cut-off wavelength of a pass area intended to pass the contiguous set of image carrying wavelengths when normally incident to the filter.

12. The laser display system according to claim 10, wherein the shifting areas comprise a majority of bandwidth within a pass area.

13. The laser display system according to claim 10, wherein the shifting areas comprise a majority of bandwidth within each pass area of a filter.

14. 3D viewing glasses comprising a left eye filter and a right eye filter, the left eye filter configured to transmit sets of projected narrowband wavelengths corresponding to left views of a 3D images rendered by the image rendering device, the right eye filter configured to transmit sets of narrowband wavelengths corresponding to a right views of the 3D images rendered by the image rendering device, the filters configured to transmit their corresponding sets of projected narrowband wavelengths to a viewer when viewed through the glasses at normal angles of incident and when viewed through the glasses at off-normal angles of incident;

wherein a longest wavelength of each set of projected narrowband wavelengths is transmitted at a first position within a pass area of its corresponding filter when viewed normally and, when viewed at increasingly off-normal angles, the longest wavelength is transmitted at increasingly further positions in a shifting area of the pass area and closer to a long wavelength end of the pass area, the shifting area comprising an area that does not transmit any of the image carrying wavelengths when viewed normally; and

the projected narrowband wavelengths are laser wavelengths; and

wherein the filters comprise a plurality of tolerance pass areas each provided between a shortest of any narrowband wavelength set passed through a pass area of a filter when normally incident and a short wavelength end of the pass area.

15. The 3D viewing glasses according to claim 14, wherein bandwidths of the tolerance pass areas are not all the same.

16. The 3D viewing glasses according to claim 14, wherein pass areas of the filters entirely encompass all image carrying wavelengths of the laser display system and sets of non-image carrying wavelengths each set of non-image carrying wavelengths adjacent to at least one image carrying wavelength and a cut-off wavelength of a pass area of the filter.

17. The 3D viewing glasses according to claim 14, wherein the shifting areas of a filter comprise pass areas between a longest wavelength of a contiguous set of image carrying wavelengths and a cut-off wavelength of a pass area intended to pass the contiguous set of image carrying wavelengths when normally incident to the filter.

18. A method comprising the steps of preparing a 3D image for viewing comprising a left eye image and a right eye image, wherein the left eye image is prepared in sets of left eye projected narrowband wavelengths corresponding to pass areas in a left eye filter to be used to view the left image and the right eye image prepared in sets of right eye narrowband wavelengths corresponding to pass areas in a right eye filter, wherein the left eye and right eye images are configured to pass through the pass areas of their corresponding eye filter when viewed through the filters at normal angles of incident and when viewed through the filters at off-normal angles of incident;

wherein a longest wavelength of each set of projected narrowband wavelengths is configured to be transmitted at a first relative position within a pass area of its corresponding filter when viewed normally and, when viewed at increasingly off-normal angles, the longest wavelength is transmitted at increasingly further positions, relative to any cut-off wavelength of the pass area, in a shifting area of the pass area and closer to a long wavelength end of the pass area, the shifting area comprising an area within the pass area that did not transmit the longest wavelength of any of the projected narrowband wavelengths when viewed normally and includes relative positions within the pass area that do not transmit any of the image carrying wavelengths when viewed normally; and

the projected narrowband wavelengths are laser wavelengths; and

wherein pass areas of the filters are constructed so that, when viewed normally, the projected narrowband wavelengths are transmitted at a shortest wavelength position of the passband that also provides a predetermined amount of transmission of the light through the passband.