STEREOSCOPIC IMAGE DISPLAY APPARATUS

• US 20150370081A1
• Filed: 01/29/2014
• Published: 12/24/2015
• Est. Priority Date: 01/30/2013
• Status: Active Grant

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: KURASHIGE, Makio
• Granted Patent: US 9,766,471 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02B 27/48 Laser speckle optics
• CPC Class Codes: G02B 30/26 of the autostereoscopic type
• CPC Class Codes: G02B 30/27 involving lenticular arrays
• CPC Class Codes: G02B 5/32 Holograms used as optical elements
• CPC Class Codes: G03B 35/18 by simultaneous viewing
• CPC Class Codes: H04N 13/32 using arrays of controllable light sources; using moving apertures or moving light sources
• CPC Class Codes: H04N 13/363 using image projection screens volumetric display H04N13/388
• CPC Class Codes: H04N 13/398 Synchronisation thereof; Control thereof
• CPC Class Codes: H04N 9/3129 scanning a light beam on the display screen scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161

Abstract

A stereoscopic image display apparatus including: an optical device having an n (n≧2) number of regions provided corresponding to the n number of parallax images, respectively, each region being capable of diffusing a coherent light beam; an irradiation unit to irradiate the optical device with a coherent light beam to scan the n number of the regions; a spatial light modulator that is illuminated with a coherent light beam incident on each of positions of the optical device and then diffused, to generate a modulated image corresponding to each of the n number of regions, in sync with the scanning of the n number of regions with the coherent light beam; and a projection optical system to project the n number of parallax images generated by the modulated image onto one plane to superimpose the parallax images on one another on the one plane at different angles.

Claims

1. A stereoscopic image display apparatus comprising:

an optical device having an n (n being an integer of 2 or more) number of regions provided corresponding to the n number of parallax images, respectively, each region being capable of diffusing a coherent light beam;

an irradiation unit to irradiate the optical device with a coherent light beam to scan the n number of the regions with the coherent light beam;

a spatial light modulator that is illuminated with a coherent light beam incident on each of positions of the optical device and then diffused, to generate a modulated image corresponding to each of the n number of the regions, in sync with the scanning of the n number of the regions by the coherent light beam; and

a projection optical system to project the n number of the parallax images generated by the modulated image onto one plane so that the parallax images are superimposed on one another on the one plane at different angles.

2. The stereoscopic image display apparatus of claim 1, wherein the projection optical system comprises a diffusing member that is disposed on the one plane to diffuse a coherent light beam corresponding to the modulated image.

3. The stereoscopic image display apparatus of claim 2, wherein the diffusing member has more excellent diffusion characteristics in one direction than in another direction.

4. The stereoscopic image display apparatus of claim 3, wherein the diffusing member has more excellent diffusion characteristics in a direction perpendicular to a horizontal direction in which horizontally adjacent pixels of a stereoscopic image viewable on the one plane are aligned, than in the horizontal direction.

5. The stereoscopic image display apparatus of claim 1 further comprising a condensing optical system that that converges the n number of the parallax images generated from the modulated image onto respective regions of an optical component disposed on the projection optical system.

6. The stereoscopic image display apparatus of claim 1, wherein the optical device is a hologram recording medium, the n number of the regions being n number of rectangular regions each extending in one direction of the hologram recording medium and having an interference fringe formed therein for diffracting a coherent light beam.

7. The stereoscopic image display apparatus of claim 6, wherein the n number of the rectangular regions are arranged so that a longitudinal direction of each rectangular region is perpendicular to a horizontal direction of the diffusing surface.

8. The stereoscopic image display apparatus of claim 6, wherein the n number of the rectangular regions are closely arranged.

9. The stereoscopic image display apparatus of claim 6, wherein the irradiation unit sequentially scans the n number of the rectangular regions with a coherent light beam in a longitudinal direction of each rectangular;

and

while the irradiation unit is scanning one of the rectangular regions with a coherent light beam, the spatial light modulator continuously generates a modulated image corresponding to the one rectangular region.

10. The stereoscopic image display apparatus of claim 1 further comprising a position detector that detects a viewer'"'"'s position, wherein the irradiation unit scans only part of the n number of the regions with a coherent light beam so that a parallax image is viewed at the viewer'"'"'s position detected by the position detector.

11. The stereoscopic image display apparatus of claim 10, wherein the position detector detects a viewer'"'"'s view direction.

12. The stereoscopic image display apparatus of claim 1, wherein the irradiation unit comprises:

a light source to emit a coherent light beam; and

a scanning device to adjust a reflection angle of the coherent light beam emitted from the light source and to scan the optical device with a reflected coherent light beam.

13. The stereoscopic image display apparatus of claim 12, wherein the light source comprises a plurality of light sources that emit a plurality of coherent light beams having different wavelength ranges, the n number of the regions of the optical device being scanned with coherent light beams from the respective light sources that correspond to the n number of the regions.