Optical system having extended angular scan range

• US 20060139714A1
• Filed: 12/23/2004
• Published: 06/29/2006
• Est. Priority Date: 12/23/2004
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Gruhlke, Russell W., Matta, Farid
• Granted Patent: US 7,215,453 B2
• Time in Patent Office: Days
• US Class Current: 359/204.100
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G02B 26/123 Multibeam scanners, e.g. using multiple light sources or beam splitters
• CPC Class Codes: Y10S 359/904 Micromirror

Abstract

System and method for scanning light across a light-receiving surface. A system for scanning light across a light-receiving surface to project a scanned line on the light-receiving surface has a light beam generator for generating a plurality of light beams. A scanning mechanism simultaneously scans each light beam of the plurality of light beams across the light-receiving surface to project a different portion of the scanned line on the light-receiving surface. The scanning system can be utilized in a compact laser printer capable of printing at a high rate, and in other scanning applications.

Claims

1. A system for scanning light across a light-receiving surface to project a scanned line on the light-receiving surface, comprising:

a light beam generator for generating a plurality of light beams; and

a Micro-Electro-Mechanical System scanning mechanism for simultaneously scanning each light beam of the plurality of light beams across the light-receiving surface to project a different portion of the scanned line on the light-receiving surface.

2. The system according to claim 1, wherein the Micro-Electro-Mechanical System scanning mechanism comprises a light redirecting mechanism for redirecting the plurality of light beams from the light beam generator to the light-receiving surface.

3. The system according to claim 2, wherein the light redirecting mechanism comprises a light reflecting member.

4. The system according to claim 3, wherein the light reflecting member comprises a mirror.

5. The system according to claim 1, wherein the light beam generator comprises a plurality of light sources.

6. The system according to claim 5, wherein the plurality of light sources comprises a plurality of Vertical Cavity Surface Emitting Lasers.

7. The system according to claim 1, and further including relay optics for relaying the plurality of light beams from the light beam generator to the Micro-Electro-Mechanical System scanning mechanism.

8. The system according to claim 7, wherein the relay optics includes optics for relaying each of the plurality of light beams to impinge on the Micro-Electro-Mechanical System scanning mechanism at a different propagation angle.

9. The system according to claim 8, wherein the optics for relaying each of the plurality of light beams to impinge on the Micro-Electro-Mechanical System scanning mechanism at a different propagation angle includes a plurality of stationary mirrors.

10. The system according to claim 8, wherein the optics for relaying each of the plurality of light beams to impinge on the Micro-Electro-Mechanical System scanning mechanism at a different propagation angle includes a diffractive element.

11. The system according to claim 1, and further including light focusing structure for focusing the plurality of light beams on the light-receiving surface.

12. The system according to claim 11, wherein the light focusing structure includes at least one fΘ

lens.

13. The system according to claim 1, and further including a stitching mechanism for correcting misalignment between adjacent light beams during a scanning operation.

14. The system according to claim 13, wherein the stitching mechanism comprises a mechanism for causing light beams to overlap in stitching regions between adjacent light beams.

15. The system according to claim 14, wherein the stitching mechanism further comprises a mechanism for adjusting a combined power of adjacent light beams in stitching regions.

16. The system according to claim 15, wherein the mechanism for adjusting a combined power of adjacent light beams in stitching regions comprises one of an optical mechanism and an electronic mechanism.

17. The system according to claim 1, wherein the light-receiving surface comprises a surface of a rotating drum.

18. The system according to claim 1, wherein the system is incorporated in a laser printer.

19. The system according to claim 18, wherein the plurality of light beams comprises three light beams, each light beam providing approximately one-third of the scanned line.

20. A method for scanning light across a light-receiving surface to project a scanned line on the light-receiving surface, comprising:

generating a plurality of light beams; and

simultaneously scanning each light beam of the plurality of light beams across the light-receiving surface with a Micro-Electro-Mechanical System scanning mechanism to project a different portion of the scanned line on the light-receiving surface.

21. The method according to claim 20, wherein simultaneously scanning each light beam of the plurality of light beams across a different portion of the light-receiving surface comprises redirecting each light beam of the plurality of light beams from a light beam generator to the light-receiving surface.

22. The method according to claim 21, wherein redirecting each light beam of the plurality of light beams from a light beam generator to the light-receiving surface comprises reflecting the plurality of light beams from the light beam generator to the light-receiving surface with a Micro-Electro-Mechanical System mirror.

23. The method according to claim 20, wherein generating a plurality of light beams comprises generating a plurality of light beams from a plurality of light sources.

24. The method according to claim 20, and further including relaying each of the plurality of light beams from a light generator to impinge on a scanning mechanism at different propagation angles.

25. The method according to claim 20, and further including correcting misalignment between adjacent light beams during a scanning operation.

26. The method according to claim 20, wherein the light-receiving surface comprises the surface of a rotating drum in a laser printer.

27. A laser printer, comprising:

a drum; and

a system for scanning light across a surface of the drum to project a scanned line on the surface of the drum, the system comprising;

a light beam generator for generating a plurality of light beams; and

a Micro-Electro-Mechanical System scanning mechanism for simultaneously scanning each light beam of the plurality of light beams across a surface of the drum to project a different portion of the scanned line on the surface of the drum.

28. The laser printer according to claim 27, wherein the light beam generator comprises a plurality of Vertical Cavity Surface Emitting Lasers.

29. The laser printer according to claim 27, wherein the Micro-Electro-Mechanical System scanning mechanism comprises a mirror.

30. The laser printer according to claim 27, wherein the Micro-Electro-Mechanical System scanning mechanism prints about 32,000 lines per minute on the drum surface.