Projection display and method for displaying at least one of two-dimensional and three-dimensional scene or of content

Patent metadata

Field	Value
Publication number	US-10146180-B2
Application number	US-201514755781-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Jul 4, 2014
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

A projection device is provided for displaying at least one of a two-dimensional and three-dimensional scene or of content. The projection device comprises an illumination device, at least two spatial light modulator devices and an optical system. The illumination device comprises at least one light source for generating a holographic illumination. One of said spatial light modulator devices is designed as spatial light modulator device modulating at least the phase of the light for the holographical generation of illumination patterns. This spatial light modulator device as first spatial light modulator device is followed by a second spatial light modulator device. The optical system is disposed to illuminate the second spatial light modulator device with a predefinable light distribution generated by the first spatial light modulator device.

First claim

What is claimed is:

1. A projection device for displaying at least one of a two-dimensional and three-dimensional scene or of content comprising:
An illumination device comprising at least one light source for generating coherent light,
At least two spatial light modulator devices, where one of said spatial light modulator devices is designed as spatial light modulator device modulating at least the phase of the light for the holographical generation of illumination patterns by use of hologram data written into said spatial light modulator, said spatial light modulator device as first spatial light modulator device is followed by a second spatial light modulator device,
the first spatial light modulator device provides a phase modulation range of larger than or equal to 2π for the primary colors red, green and blue of the illumination device,
An optical system disposed to illuminate the second spatial light modulator device with a predefinable light distribution generated by the first spatial light modulator device, and
the resolution or the pixel pitch of the first spatial light modulator device and the distance between the first spatial light modulator device and the second spatial light modulator device are determined such that for all wavelengths of the illumination the dimension of one diffraction order of the first spatial light modulator device which is generated on the second spatial light modulator device does not fall below a value of the area of the second spatial light modulator device.

2. The projection device according to claim 1 , wherein the optical system comprising at least one imaging element.

3. The projection device according to claim 1 , wherein the optical system is provided close to or directly at the position of the first spatial light modulator device.

4. The projection device according to claim 1 , wherein the second spatial light modulator device is provided in or close to the Fourier plane of the first spatial light modulator device generated by the optical system.

5. The projection device according to claim 1 , wherein the at least one light source of the illumination device comprises a sufficiently large coherence for reconstruction of the hologram encoded on the first spatial light modulator device.

6. The projection device according to claim 1 , wherein the at least one light source of the illumination device comprises a sufficiently small coherence for reduction of speckle.

7. The projection device according to claim 1 , wherein a diffuser device is provided for reduction of speckle in the light distribution of the illumination on the second spatial light modulator device.

8. The projection device according to claim 1 , wherein a correction intensity factor is provided for compensating for blur or for smoothing of the illumination intensity from the hologram.

9. The projection device according to claim 1 , further comprising a further spatial light modulator device, said further spatial light modulator device is arranged in parallel to the first spatial light modulator device for illumination the second spatial light modulator device.

10. The projection device according to claim 9 , wherein the same at least one light source is used for the holographical generation of illumination patterns with the first spatial light modulator device and for illumination with the further spatial light modulator device.

11. The projection device according to claim 9 , wherein the illumination device comprises at least two light sources, where at least one of the at least two light sources is used for the holographical generation of illumination patterns with the first spatial light modulator device whereas at least one other light source of the at least two light sources is used for illumination with the further spatial light modulator device.

12. The projection device according to claim 11 , wherein at least one of the at least two light sources comprises a sufficiently large coherence for reconstruction of the hologram encoded on the first spatial light modulator device whereas at least one other of the at least two light sources is an incoherent light source for incoherent illumination with the further spatial light modulator.

13. The projection device according to claim 9 , wherein a switch device is provided for switching from the first spatial light modulator device to the further spatial light modulator device and vice versa for the selection of the more efficient way of illumination of the second spatial light modulator device, depending on the actual content to be displayed on the second spatial light modulator device.

14. The projection system according to claim 9 , wherein a switch device is provided, the switch device is designed as a variable switch device for switching from the illumination device to both the first spatial light modulator device and the further spatial light modulator device for directing a predefined quantity of light emitted by the illumination device to the first spatial light modulator device and a predefined quantity of light to the further spatial light modulator device, depending on the actual content to be displayed on the second spatial light modulator device.

15. The projection device according to claim 9 , wherein the further spatial light modulator device is designed as DPL (digital light processing) type spatial light modulator device or as DMD (digital micro mirror device) type spatial light modulator device.

16. The projection device according to claim 1 , wherein the first spatial light modulator device is designed as MEMS (micro electro mechanical system) type spatial light modulator device comprising tip mirror elements for modulating the phase of the light in an analogue manner.

17. The projection device according to claim 1 , wherein the second spatial light modulator device is designed as DPL (digital light processing) type spatial light modulator device or as DMD (digital micro mirror device) type spatial light modulator device.

18. A method for displaying at least one of a two-dimensional and three-dimensional scene or of content, the method comprising:
generating coherent light by an illumination device comprising at least one light source,
predefining a light distribution depending on the brightness distribution of a scene or of content to be displayed,
holographically generating said predefinable light distribution by calculating a hologram and encoding said hologram into a first spatial light modulator device designed as spatial light modulator device modulating at least the phase of the light and arranging a second spatial light modulator device which follows the first spatial light modulator device, seen in the propagation of light,
illuminating the second spatial light modulator device with said predefinable light distribution according to the hologram generated by the first spatial light modulator device by an optical system, and
modulating a light field having the predefinable light distribution incident on the second spatial light modulator device by said second spatial light modulator device in such a way as displaying the reconstruction of that scene.

19. The method according to claim 18 , wherein the optical system is disposed in such a way that the Fourier plane is generated at or close to the second spatial light modulator device.

20. The method according to claim 18 , wherein the predefinable light distribution for illumination of the second spatial light modulator device is adapted within the area of the second spatial light modulator d

Assignees

• Seereal Tech S A

Inventors

• Leister Norbert
• Fuetterer Gerald
• Kroll Bo
• Stolle Hagen

Classifications

• H04N9/3197

  using light modulating optical valves · CPC title

• H04N9/3164

  using multiple light sources · CPC title

• G03H1/32

  Systems for obtaining speckle elimination · CPC title

• G03H1/2286

  Particular reconstruction light (G03H1/24 takes precedence); Beam properties · CPC title

• H04N9/3161

  using laser light sources (using laser beams scanning the display screen H04N9/3129) · CPC title