Three dimensional image projector

• US 8,998,427 B2
• Filed: 10/15/2012
• Issued: 04/07/2015
• Est. Priority Date: 01/25/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: DeCusatis, Casimer M.
• Primary Examiner(s): Ton, Toan
• Assistant Examiner(s): Cruz, Magda
• Application Number:
  US13/651,780
• Publication Number:
  US 20130188146A1
• Time in Patent Office: 904 Days
• Field of Search: 353/94, 353/98, 353/99, 362/349.02, 362/311.02, 372/50.12
• US Class Current: 353/98
• CPC Class Codes: G02B 27/1033 having a single light modulator for all colour channels
• CPC Class Codes: G02B 30/24 involving temporal multiplexing, e.g. using sequentially activated left and right shutters
• CPC Class Codes: G02B 30/25 using polarisation techniques
• CPC Class Codes: G03B 21/2033 LED or laser light sources
• CPC Class Codes: G03B 21/2066 Reflectors in illumination beam in projection beam G03B21/28
• CPC Class Codes: G03B 33/12 using beam-splitting or beam-combining systems, e.g. dichroic mirrors
• CPC Class Codes: G03B 35/16 by sequential viewing
• CPC Class Codes: G03B 35/26 using polarised or coloured light separating different viewpoint images
• CPC Class Codes: H04N 13/341 using temporal multiplexing
• CPC Class Codes: H04N 13/363 using image projection screens volumetric display H04N13/388
• CPC Class Codes: H04N 13/365 using digital micromirror devices [DMD]

Abstract

A method of projecting an image is provided. The method includes the step of providing a first light source, the first light source emitting light at a first polarization. A second light source is provided adjacent the first light source, the second light source emitting light at a second polarization. A digital mirror device is provided (DMD), the DMD having a first axis. A mirror is provided optically disposed between the first light source, the second light source and the DMD, the mirror being adjacent the DMD. A first light is emitted from the first light source. The first light is reflected with the mirror onto the DMD. A second light is emitted from the second light source after the first light is emitted. The second light is reflected with the mirror onto the DMD.

Claims

1. A method comprising:

providing a first light source, the first light source emitting light at a first polarization;

providing a second light source adjacent the first light source, the second light source emitting light at a second polarization;

providing a digital mirror device (DMD), the DMD having a first axis;

providing a mirror optically disposed between the first light source, the second light source and the DMD, the mirror being adjacent the DMD;

emitting a first light from the first light source;

reflecting the first light with the mirror onto the DMD having a first image thereon;

emitting a second light from the second light source after the first light is emitted;

reflecting the second light with the mirror onto the DMD having a second image thereon, the second image being offset from the first image; and

forming a three dimensional image from the first light and second light reflected from the DMD.

2. The method of claim 1 further comprising:

providing a projection lens adjacent the DMD, the projection lens having a second axis, wherein the second axis is offset from the first axis;

emitting the first light reflected from the DMD through the projection lens; and

,

emitting the second light reflected from the DMD through the projection lens.

3. The method of claim 1 wherein:

the first light source includes a first green laser diode, a first blue laser diode and a first red laser diode; and

,

the second light source includes a second green laser diode, a second blue laser diode and a second red laser diode.

4. The method of claim 1 wherein the first light source, the second light source and the DMD use less than or equal to 30 milliwatts of electrical power.

5. A method comprising:

providing a first light source, the first light source emitting light at a first polarization;

providing a second light source adjacent the first light source, the second light source emitting light at a second polarization;

providing a digital mirror device (DMD), the DMD having a first axis;

providing a mirror optically disposed between the first light source, the second light source and the DMD the mirror being adjacent the DMD;

emitting a first light from the first light source;

reflecting the first light with the mirror onto the DMD;

emitting a second light from the second light source after the first light is emitted; and

,

reflecting the second light with the mirror onto the DMD;

providing a projection lens adjacent the DMD, the projection lens having a second axis, wherein the second axis is offset from the first axis;

emitting the first light reflected from the DMD through the projection lens;

emitting the second light reflected from the DMD through the projection lens;

transmitting a first modulation signal to the first light source and the second light source;

transmitting a second modulation signal to the DMD; and

,

wherein the first modulation signal is two times a frequency of the second modulation signal.

6. The method of claim 5 further comprising:

forming a first image on the DMD when the first light is reflected by the mirror;

forming a second image on the DMD when the second light is reflected by the mirror; and

forming a three dimensional image from the first light and second light reflected by the DMD.

7. The method of claim 6 further comprising:

distributing the first light prior to reflecting with the mirror; and

distributing the second light prior to reflecting with the mirror.

8. The method of claim 7 further comprising:

providing the DMD with a first axis substantially perpendicular to the plane of the DMD;

providing a projection lens having a second axis substantially parallel to and offset from the first axis; and

emitting the first light and the second light through the projection lens after reflecting off of the DMD.

9. The method of claim 6 further comprising:

providing a first collimating lens optically coupled to the first light source and the second light source;

providing a second collimating lens optically coupled to the first light source and the second light source; and

,

providing a third collimating lens optically coupled to the first light source and the second light source.

10. A method comprising:

providing a first light source, the first light source emitting light at a first polarization;

providing a second light source adjacent the first light source, the second light source emitting light at a second polarization;

providing a digital mirror device (DMD), the DMD having a first axis;

providing a mirror optically disposed between the first light source, the second light source and the DMD, the mirror being adjacent the DMD;

emitting a first light from the first light source;

reflecting the first light with the mirror onto the DMD;

emitting a second light from the second light source after the first light is emitted; and

,

reflecting the second light with the mirror onto the DMD;

the first light source includes a first green laser diode, a first blue laser diode and a first red laser diode; and

,

the second light source includes a second green laser diode a second blue laser diode and a second red laser diode;

providing a first collimating lens optically coupled to the first green laser diode and the second green laser diode;

providing a second collimating lens optically coupled to the first blue laser diode and the second blue laser diode; and

,

providing a third collimating lens optically coupled to the first red laser diode and the second red laser diode.

11. The method of claim 10 further comprising:

providing a first dichroic mirror adjacent the first collimating lens;

providing a second dichroic mirror adjacent the second collimating lens; and

,

providing a third dichroic mirror adjacent the third collimating lens.

12. The method of claim 10 further comprising:

forming a first image on the DMD when the first light is reflected by the mirror;

forming a second image on the DMD when the second light is reflected by the mirror; and

forming a three dimensional image from the first light and second light reflected by the DMD.

13. The method of claim 12 further comprising:

distributing the first light prior to reflecting with the mirror; and

distributing the second light prior to reflecting with the mirror.

14. The method of claim 13 further comprising:

providing the DMD with a first axis substantially perpendicular to the plane of the DMD;

providing a projection lens having a second axis substantially parallel to and offset from the first axis; and

emitting the first light and the second light through the projection lens after reflecting off of the DMD.

15. The method of claim 12 further comprising:

transmitting a first modulation signal to the first light source and the second light source;

transmitting a second modulation signal to the DMD; and

,

wherein the first modulation signal is two times a frequency of the second modulation signal.

16. A method comprising:

providing a first light source, the first light source emitting light at a first polarization;

providing a second light source adjacent the first light source, the second light source emitting light at a second polarization;

providing a digital mirror device (DMD), the DMD having a first axis;

providing a mirror optically disposed between the first light source, the second light source and the DMD, the mirror being adjacent the DMD;

emitting a first light from the first light source;

reflecting the first light with the mirror onto the DMD;

emitting a second light from the second light source after the first light is emitted; and

,

reflecting the second light with the mirror onto the DMD;

wherein the first light source, the second light source and the DMD are arranged within a space about 5-10.5 mm in height, about 20-37 mm in width and about 20-37 mm in length.

17. The method of claim 16 further comprising:

forming a first image on the DMD when the first light is reflected by the mirror;

forming a second image on the DMD when the second light is reflected by the mirror; and

forming a three dimensional image from the first light and second light reflected by the DMD.

18. The method of claim 17 further comprising:

distributing the first light prior to reflecting with the mirror; and

distributing the second light prior to reflecting with the mirror.

19. The method of claim 18 further comprising:

providing the DMD with a first axis substantially perpendicular to the plane of the DMD;

providing a projection lens having a second axis substantially parallel to and offset from the first axis; and

emitting the first light and the second light through the projection lens after reflecting off of the DMD.

20. The method of claim 17 further comprising:

transmitting a first modulation signal to the first light source and the second light source;

transmitting a second modulation signal to the DMD; and

,

wherein the first modulation signal is two times a frequency of the second modulation signal.