Optical element, optical system using optical element, and optical device with optical element

• US 6,337,772 B2
• Filed: 02/23/2001
• Issued: 01/08/2002
• Est. Priority Date: 08/22/1996
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kawano, Kenji, Iida, Seiji, Sekita, Makoto, Uehara, Tsukasa
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): Lucas, Michael A.
• Application Number:
  US09/792,242
• Publication Number:
  US 20010009477A1
• Time in Patent Office: 319 Days
• Field of Search: 359/631, 359/627, 359/628, 359/629, 359/630, 359/676
• US Class Current: 359/631
• CPC Class Codes: G02B 17/0848 off-axis or unobscured systems in which not all of the mirrors share a common axis of rotational symmetry, e.g. at least one of the mirrors is warped, tilted or decentered with respect to the other elements
• CPC Class Codes: G02B 17/086 wherein the system is made of a single block of optical material, e.g. solid catadioptric systems
• CPC Class Codes: G02B 17/0896 with variable magnification or multiple imaging planes, including multispectral systems systems with only refractive elements G02B15/14

Abstract

In an optical element (B1) prepared by integrally forming, on surfaces of a transparent member, a refracting surface (R2) for receiving a light beam, a plurality of reflecting surfaces (R3, R4, R5) with curvatures, and a refracting surface (R6) for outputting the light beam reflected by the plurality of reflecting surfaces, a reference portion (7) for defining the position of the optical element in a predetermined direction with respect to a Y′-Z′ plane including an incident reference axis (5) and an exit reference axis (5) of at least one reflecting surface of the optical element (B1) is formed on the optical element.

Claims

1. An optical system comprising an optical element prepared by integrally forming, on surfaces of a transparent member, a refracting surface for receiving a light beam, a plurality of reflecting surfaces with curvatures, and a refracting surface for outputting the light beam reflected by the plurality of reflecting surfaces, said optical element having a fitting portion formed integrally therewith, said fitting portion being fitted on guide means for defining a moving direction of said optical element, and said optical element being arranged to be movable in the defined direction.

2. The system according to claim 1, wherein a central axis of said fitting portion is set to be parallel to a plane including an incident and exit reference axes of at least one reflecting surface of said optical element.

3. The system according to claim 1, wherein a central axis of said fitting portion is in a plane including an incident and exit reference axes of at least one reflecting surface of said optical element.

4. An optical device comprising an optical element in which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, said optical element being fixed to a support member at one end portion thereof.

5. The device according to claim 4, wherein said optical element comprises a projection at a position separated from the refracting and reflecting surfaces of the light beam, and said projection is fixed to said support member.

6. The device according to claim 5, wherein projection of said optical element projects in a direction perpendicular to a longitudinal direction of said optical element.

7. The device according to claim 6, wherein a slit portion or a groove portion is formed on said projection of said optical element so as not to adversely influence refraction or reflection of the light beam when said optical element is fixed to said support member.

8. The device according to claim 5, wherein said optical element has a gate used upon forming said optical element at a fixing portion side thereof.

9. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, at least one optical element being fixed to a support member at one end portion thereof.

10. The device according to claim 9, wherein said optical element comprises a projection at a position separated from the refracting and reflecting surfaces of the light beam, and said projection is fixed to said support member.

11. The device according to claim 10, wherein said projection of said optical element projects in a direction perpendicular to a longitudinal direction of said optical element.

12. The device according to claim 11, wherein a slit portion or a groove portion is formed on said projection of said optical element so as not to adversely influence refraction or reflection of the light beam when said optical element is fixed to said support member.

13. The device according to claim 10, wherein said optical element has a gate used upon forming said optical element at a fixing portion side thereof.

14. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface,

wherein at least one optical element of said zoom optical system is fixed to a support member at one end portion thereof, has a plurality of projections in a longitudinal direction thereof, and is placed on an extended portion of said support member via said plurality of projections.

15. The device according to claim 14, wherein said plurality of projections of said optical element are formed to be separated in the longitudinal direction and a widthwise direction of said optical element.

16. The device according to claim 14, wherein said support member comprises a butt portion for receiving said plurality of projections of said optical element so as to attain high-precision positioning.

17. An optical device comprising an optical element in which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface,

wherein said optical element has a plurality of projections in a longitudinal direction thereof, is arranged on a support member via said plurality of projections, and is fixed to said support member by adhering one of said plurality of projections to said support member.

18. The device according to claim 17, wherein said support member comprises a butt portion for receiving said plurality of projections of said optical element so as to attain high-precision positioning.

19. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, and driving means for driving said zoom optical system to attain zooming,

wherein the zooming is done by moving first and second movable bases along a guide member in an optical axis direction in which light leaving one optical element mounted on said first movable base of said plurality of optical elements of said zoom optical system enters another optical element mounted on said second movable base, and said one optical element and said other optical element are respectively attached to said first and second movable bases at one-end portions thereof.

20. The device according to claim 19, wherein said guide member is arranged in the vicinity of the optical axis to be parallel to the optical axis.

21. The device according to claim 19, wherein said first and second movable bases use a common guide member.

22. The device according to claim 21, wherein said one optical element is arranged to extend from one side to the other side of said guide member with a longitudinal direction thereof being perpendicular to said guide member and is fixed to said first movable base at the other side thereof, and said other optical element is arranged to extend from one side to the other side of said guide member with a longitudinal direction thereof being perpendicular to said guide member and is fixed to said second movable base at one side thereof.

23. The device according to claim 19, wherein said guide member comprises a guide rail which fits into holes formed on said first and second moveable bases.

24. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, and driving means for driving said zoom optical system to attain zooming,

wherein the zooming is done by moving first and second movable bases along a guide member in an optical axis direction in which light leaving one optical element mounted on said first movable base of said plurality of optical elements of said zoom optical system enters another optical element mounted on said second movable base, and an attachment position of said one optical element to said first movable base and an attachment position of said other optical element to said second movable base are present on the optical axis side of the individual optical elements.

25. The device according to claim 24, wherein said guide member is arranged in the vicinity of the optical axis to be parallel to the optical axis.

26. The device according to claim 24, wherein said first and second movable bases use a common guide member.

27. The device according to claim 26, wherein said one optical element is arranged to extend from one side to the other side of said guide member with a longitudinal direction thereof being perpendicular to said guide member and is fixed to said first movable base at the other side thereof, and said other optical element is arranged to extend from one side to the other side of said guide member with a longitudinal direction thereof being perpendicular to said guide member and is fixed to said second movable base at one side thereof.

28. The device according to claim 24, wherein said guide member comprises a guide rail which fits into holes formed on said first and second movable bases.

29. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, and driving means for driving said zoom optical system to attain zooming,

wherein the zooming is done by moving first and second movable bases along a guide member in an optical axis direction in which light leaving one optical element mounted on said first movable base of said plurality of optical elements of said zoom optical system enters another optical element mounted on said second movable base, and an attachment position of said one optical element to said first movable base and an attachment position of said other optical element to said second movable base are symmetrical positions with respect to said guide member.

30. The device according to claim 29, wherein said guide member is arranged in the vicinity of the optical axis to be parallel to the optical axis.

31. The device according to claim 29, wherein said first and second movable bases use a common guide member.

32. The device according to claim 31, wherein said one optical element is arranged to extend from one side to the other side of said guide member with a longitudinal direction thereof being perpendicular to said guide member and is fixed to said first movable base at the other side thereof, and said other optical element is arranged to extend from one side to the other side of said guide member with a longitudinal direction thereof being perpendicular to said guide member and is fixed to said second movable base at one side thereof.

33. The device according to claim 29, wherein said guide member comprises a guide rail which fits into holes formed on said first and second movable bases.

34. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, and driving means for driving said zoom optical system to attain zooming,

wherein a fixing position of a first optical element to a base of said zoom optical system, a fixing position of a second optical element to a first movable base, and a fixing position of a third optical element to a second movable base are located on a side of a guide member common to said first and second movable bases in a longitudinal direction of the optical elements.

35. The device according to claim 34, wherein said guide member comprises a guide rail which fits into holes formed on said first and second movable bases.

36. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, and driving means for driving said zoom optical system to attain zooming,

wherein a first driving source of said driving means is arranged among first, second, and third optical elements of said zoom optical system, and a second driving source of said driving means is arranged between the second and third optical elements.

37. The device according to claim 36, wherein said second driving source of said driving means is arranged between the second and third optical elements.

38. The device according to claim 37, wherein said first and second driving sources comprise motors.

39. The device according to claim 38, wherein shafts of the motors are arranged to be parallel to a moving plane of the optical elements for attaining the zooming.

40. The device according to claim 39, wherein a power transmission mechanism between the shafts of the motors and the optical elements is a gear mechanism or a cam mechanism or a mechanism in which a screw and a rack mesh with each other.

41. The device according to claim 38, wherein shafts of the motors are arranged to be perpendicular to a moving plane of the optical elements for attaining the zooming.

42. The device according to claim 41, wherein a circuit board is arranged between the motors and a base for supporting the motors and the optical elements.

43. An optical device comprising a zoom optical system having a plurality of optical elements in each of which a light beam enters said optical element via one refracting surface, is repetitively reflected by a plurality of reflecting surfaces, and leaves said optical element from another refracting surface, and driving means for driving said zoom optical system to attain zooming,

wherein the zooming is done by moving first and second movable bases along a guide member in an optical axis direction in which light leaving one optical element of said plurality of optical elements of said zoom optical system enters another optical element, and said guide member is arranged in the vicinity of the optical axis.

44. The device according to claim 43, wherein said one and other optical elements use a common guide member.

45. The device according to claim 43, wherein said driving means transmits a driving force to said one and other optical elements at a position in the vicinity of said guide member.

46. The device according to claim 43, wherein said guide member comprises a guide rail that fits into holes formed on support members for supporting the optical elements.