Projector with laser illumination elements offset along an offset axis

• US 9,116,421 B1
• Filed: 01/07/2013
• Issued: 08/25/2015
• Est. Priority Date: 01/07/2012
• Status: Active Grant

• Current Assignee: Greelight Optics, LLC
• Original Assignee: Greenlight Optics LLC
• Inventors: Rutherford, Todd S.
• Primary Examiner(s): Reilly-Diakun, Jori S
• Application Number:
  US13/735,663
• Time in Patent Office: 960 Days
• Field of Search: 353 30- 31, 353/33, 353/37, 353 50- 51, 353 77- 78, 353/81, 353/94, 353 98- 99, 348/744, 348/798, 362230-231, 362234-237, 362/241, 362244-245, 362/249.06, 362/249.14
• US Class Current: 1/1
• CPC Class Codes: G02B 27/106 for splitting or combining a plurality of identical beams or images, e.g. image replication
• CPC Class Codes: G02B 27/143 using macroscopically faceted or segmented reflective surfaces
• CPC Class Codes: G02B 27/48 Laser speckle optics
• CPC Class Codes: G03B 21/2013 Plural light sources
• 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 21/208 Homogenising, shaping of the illumination light
• CPC Class Codes: H04N 9/3152 for shaping the light beam beam shaping per se G02B27/09
• CPC Class Codes: H04N 9/3161 using laser light sources using laser beams scanning the display screen H04N9/3129

Abstract

An optical system has projector optics aligned on a projection axis that is orthogonal to an offset axis. A first laser is positioned in a first plane orthogonal to the projection axis. First folding optics are positioned in the first plane to fold a first beam from the first laser to a first portion of the projector optics. A second laser is in a second plane parallel to, and offset along the offset axis from, the first plane. Second folding optics is positioned in the second plane to fold a second beam from the second laser to a second portion of the projector optics to synthesize the first and second beam.

Claims

1. An illumination system for spatially multiplexing and synthesizing multiple laser beam sources, comprising:

illumination optics aligned on a projection axis that is orthogonal to an offset axis;

a first laser in a first plane orthogonal to the projection axis;

first folding optics positioned in the first plane to fold a first beam from the first laser to a first portion of the illumination optics comprising a first segment of a stacked collimating lens;

a second laser in a second plane parallel to, and offset along the offset axis from, the first plane;

second folding optics positioned in the second plane to fold a second beam from the second laser to a second portion of the illumination optics comprising a second segment of the stacked collimating lens,

wherein illumination optics synthesizes the first and second beam by spatial multiplexing.

2. The illumination system of claim 1, wherein the first and second folding optics comprise folding mirrors.

3. The illumination system of claim 1, wherein the first and second folding optics comprise prisms.

4. The illumination systems of claim 1, wherein at least one of the first and second laser is positioned in a right angle to the projection axis.

5. The illumination system of claim 1, wherein the projection optics further comprises a diffuser, multiple lens array and relay lens downstream to the stacked collimator lenses.

6. The illumination system of claim 5, further comprises a condenser lens disposed between the relay lens and at least one laser.

7. The illumination system of claim 1, further comprising:

a third laser in a third plane parallel to, and offset along the offset axis from, the first and second planes;

third folding optics positioned in the third plane to fold a third beam from the third laser to a third portion of the illumination optics,

wherein illumination optics synthesizes the first, second and third beams.

8. The illumination system of claim 7, wherein the first, second and third beams comprise red, green and blue laser beams.

9. The illumination system of claim 7, further comprising:

a fourth laser in a fourth plane parallel to, and offset along the offset axis from, the first, second and third planes;

fourth folding optics positioned in the fourth plane to fold a fourth beam from the fourth laser to a fourth portion of the illumination optics,

wherein illumination optics synthesizes the first, second, third and fourth beams.

10. The illumination system of claim 9, wherein secondary optics are disposed in front of one or more of the lasers;

wherein the secondary optics reduce the beam divergence of the lasers that are placed farther from the collimating lenses.

11. The illumination system of claim 7, wherein a first laser emits green light and has a radiant flux range of from about 40 to about 1000 mW;

a second laser emits red light and has a radiant flux range of from about 40 to about 1000 mW; and

a third laser emits blue light and has a radiant flux range of from about 40 to about 1000 mW.

12. A projector comprising:

the illumination system set forth in claim 1;

a light guiding device;

a light source side optical system;

a display device;

a projection side optical system; and

projector control device, wherein a light gathering optical system of the light source apparatus gathers light source light on to an incident plane of the light guiding device.

13. The projector of claim 12, further comprising a plurality of light redirectors.

14. The projector of claim 13, wherein each light redirector is any one of the group consisting of a total internal reflection prism, a polarization beam splitter, color mixer, and a plurality of mirrors.

15. The illumination system of claim 1, wherein the first and second segments of stacked collimating lens each have a center axis that directs a received beam to a center of curvature for each segment of the stacked collimator lens in a displaced, stacked alignment.