Optical scanner

• US 6,429,423 B1
• Filed: 04/19/2000
• Issued: 08/06/2002
• Est. Priority Date: 05/03/1999
• Status: Expired due to Fees

• Current Assignee: ELOP Electro-Optics Industries Limited
• Original Assignee: ELOP Electro-Optics Industries Limited
• Inventors: Friedland, Igor, Shechterman, Mark
• Primary Examiner(s): Kim, Robert H.
• Assistant Examiner(s): THOMAS, COURTNEY D
• Application Number:
  US09/551,955
• Time in Patent Office: 839 Days
• Field of Search: 250/234, 250/208.1, 250/235, 250/236, 359/197, 359/201, 359/202, 359/204, 359/212, 359/217, 359/220, 359/872, 359/873, 359/874, 359/876
• US Class Current: 250/234
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification
• CPC Class Codes: G02B 26/108 having one or more prisms as scanning elements
• CPC Class Codes: G02B 26/129 Systems in which the scanning light beam is repeatedly reflected from the polygonal mirror
• CPC Class Codes: G02B 27/0031 for scanning purposes
• CPC Class Codes: H02K 33/18 with coil systems moving upon intermittent or reversed energisation thereof by interaction with a fixed field system, e.g. permanent magnets

Abstract

The invention provides a device for linear scanning, including at least one reflecting element whereby an incident beam of light undergoes at least two reflections; at least one optical system comprising an objective capable of forming an image of an object, the objective, depending on the respective direction of the light beam, defining a pre-objective scanning space and a post-objective scanning space; a mounting structure for the at least one reflecting element; drive means for causing the mounting structure to perform a movement; and a light-detecting element for detecting the incident beam of light, or an element for producing light, wherein, with light-detecting, scanning takes place in the post-objective space, and with light-producing, scanning takes place in the pre-objective space.

Claims

1. A device for linear scanning, comprising:

a reflecting element selected from the group consisting of a prism and a pair of angle mirrors arranged and adapted so that an incident beam of light undergoes at least two reflections;

at least one optical system comprising an objective which forms an image of an object, said objective, depending on the respective direction of said light beam, defining a pre-objective scanning space and a post-objective scanning space;

a mounting structure for said at least one reflecting element;

drive means for moving said mounting structure in one of a linearly reciprocating motion and a continuously rotating motion; and

a light-detecting element for detecting said incident beam of light,

wherein, with light-detecting, scanning takes place in said post-objective space.

2. The device as claimed in claim 1, wherein said movement is a linearly reciprocating movement.

3. The device as claimed in claim 1, wherein said movement is a continuously rotating movement.

4. The device as claimed in claim 1, wherein said light-reflecting element is at least one right angle prism.

5. The device as claimed in claim 1, wherein said light-reflecting element is at least one pair of mirrors including between them an angle less than 180°

.

6. The device as claimed in claim 3, wherein said light-reflecting element is comprised of a plurality of pairs of mirrors arranged in an annular configuration.

7. The device as claimed in claim 2, wherein said drive means is a moving-coil galvanometric drive.

8. The device as claimed in claim 7, wherein the coil of said moving-coil drive means is an integral part of a printed circuit board.

9. The device as claimed in claim 3, wherein said drive means is an electric motor causing said mounting structure to rotate.

10. The device as claimed in claim 2, wherein said movement is opposed by the restoring force of at least one elastically resilient member.

11. The device as claimed in claim 1, wherein said optical system produces at least one intermediate image, with scanning being performed at the location of said intermediate image and relay optics transmitting said image to said light-detecting element.

12. The device as claimed in claim 1, further comprising a position sensor.

13. The device as claimed in claim 12, wherein said position sensor includes a light source and a bi-cell photodetector stationary relative to a carrying member,

wherein a differential output of the two cells of said bi-cell photodetector vary as a function of an instantaneous position of said reflecting element.

14. The device as claimed in claim 12, wherein said position sensor is a rotary encoder coupled to an electric motor.

23. The device of claim 12, wherein said drive means is an electric motor causing said mounting structure to rotate.

15. A device for linear scanning, comprising:

a reflecting element selected from the group consisting of a prism and a pair of angle mirrors arranged and adapted so that an incident beam of light undergoes at least two reflections;

at least one optical system comprising an objective which forms an image of an object, said objective, depending on the respective direction of said light beam, defining a pre-objective scanning space and a postobjective scanning space;

a mounting structure for said at least one reflecting element;

drive means for moving said mounting structure in one of a linearly reciprocating motion and a continuously rotating motion; and

an element for producing light,

wherein, with light-producing, scanning takes place in said pre-objective space.

16. The device of claim 15, wherein said movement is a linearly reciprocating movement.

17. The device of claim 15, wherein said movement is a continuously rotating movement.

18. The device of claim 15, wherein said light-reflecting element is at least one right angle prism.

19. The device of claim 15, wherein said light-reflecting element is at least one pair of mirrors including between them an angle less than 180°

.

20. The device of claim 17, wherein said light-reflecting element comprises a plurality of pairs of mirrors arranged in an annular configuration.

21. The device of claim 16, wherein said drive means is a moving-coil galvanometric drive.

22. The device of claim 21, wherein the coil of said moving-coil drive means is an integral part of a printed circuit board.

24. The device of claim 16, wherein said movement is opposed by the restoring force of at least one elastically resilient member.

25. The device of claim 15, further comprising a position sensor.

26. The device of claim 25, wherein said position sensor includes a light source and a bi-cell photodetector stationary relative to a carrying member,

wherein a differential output of the two cells of said bi-cell photodetector varies as a function of an instantaneous position of said reflecting element.

27. The device of claim 25, wherein said position sensor is a rotary encoder coupled to an electric motor.