Flying spot endoscope

• US 5,103,497 A
• Filed: 01/03/1991
• Issued: 04/07/1992
• Est. Priority Date: 11/14/1989
• Status: Expired due to Fees

• Current Assignee: John W. Hicks
• Original Assignee: John W. Hicks
• Inventors: Hicks, John W.
• Primary Examiner(s): Lee, John D.
• Assistant Examiner(s): Ngo, John
• Application Number:
  US07/637,157
• Time in Patent Office: 460 Days
• Field of Search: 350/96.24-96.27, 350/96.33, 355/1
• US Class Current: 385/117
• CPC Class Codes: G02B 23/26 using light guides for illumination G02B23/2469
• CPC Class Codes: G02B 26/103 having movable or deformable optical fibres, light guides or waveguides as scanning elements light guides per se G02B6/00
• CPC Class Codes: G02B 6/08 with fibre bundle in form of plate

Abstract

A fiber optic scanning system having a multifiber. The multifiber having a first group of cores having an index of refraction N1 and a second group of cores having an index of refraction N2. The cores being positioned in a matrix. The cores of the groups being arrayed so that the adjacent cores of any core are members of the other group. The index difference between N1 and N2 being great enough to produce substantial mismatch in the cores and to substantially reduce cross talk between any core of one group and any core of the other group.

Claims

1. A fiber optic scanning system comprising:

a multifiber having a proximal end and a distal end, the multifiber having a first group of cores having an index of refraction N₁ ;

a second group of cores having an index of refraction N₂, the cores being positioned in a matrix;

the cores of the groups being arrayed so that the adjacent cores of any core are members of the other group;

the indices N₁ and N₂ being greater than the index of the surrounding matrix and the index difference between N₁ and N₂ being great enough to produce substantial mismatch in the propagation constants in the cores and to substantially reduce cross talk between any core of one group and any core of the other group;

means to scan the distal end of the cores in at least one dimension whereby said cores cyclically scan at least a line segment of an image formed in an image plane; and

means to transmit an optical signal train to detect and to convert the optical signal into an electrical signal train and to modulate the electrical signal train into an electron beam which scans at the proximal end in a pattern analogous to the scan at the distal end.

2. A system of claim 1 wherein the index difference between N₁ and N₂ is at least about 0.02.

3. The system of claim 1 wherein the multifiber comprises at least a two dimension array and includes:

third and fourth groups of cores having indices of refractions N₃ and N₄, the indices of refraction of N₃ and N₄ being different from one another and from either of the indices of refraction of the cores N₁ and N₂, the index of refraction between the higher and lower index cores being at least about 0.06.

4. The system of claim 1 which comprises:

distal optics to form an image of an object onto the distal end of said fiber.

5. The system of claim 4 wherein the distal optics is a spherical lens.

6. The system of claim 5 wherein the distal lens includes a circular shoulder and a smaller hemispheric lens extends from the shoulder.

7. The system of claim 1 which comprises:

proximal optics to project the image at the proximal end of the fiber.

8. The system of claim 1 which comprises:

means to illuminate the object to be viewed.

9. The system of claim 1 which includes:

means to scan the multiple cores across the image formed in the image plane to provide sequential viewing of substantially the entire area of the image.

10. The system of claim 1 which comprises:

means to reconstruct and to display the scanned image.

11. The system of claim 10 wherein the means to display is a cathode ray tube.

12. The system of claim 1 wherein the means for reconstruction comprises:

means to scan the proximal and distal ends in synchronism.

13. The system of claim 1 which comprises:

means for scanning rotatably about the longitudinal axis of the multifiber.

14. The system of claim 1 where the multifiber carries the light to illuminate the object whose image is formed in the image plane.

15. A fiber optic scanning system comprising:

a multifiber having a proximal end and a distal end and having a plurality of cores arrayed in a linear dimension, the cores phase mismatched to reduce cross talk and further comprising;

a first group of cores having an index of refraction N₁ ;

a second group of cores having an index of refraction N₂, the cores being positioned in a matrix;

the cores of the groups being arrayed so that the adjacent cores of any core are members of the other group;

the indices N₁ and N₂ being greater than the index of the surrounding matrix and the index difference between N₁ and N₂ being great enough to produce substantial mismatch in the propagation constants in the cores and to substantially reduce cross talk between any core of one group and any core of the other group;

means to scan the distal end of the cores in at least one dimension whereby said cores cyclically scan at least a line segment of an image formed in an image plane;

means to scan along an orthogonal dimension; and

means to display the scanned image at the proximal end.

16. The system of claim 15 wherein the index difference between N₁ and N₂ is at least about 0.02.

17. The system of claim 15 which comprises:

distal optics to form an image of an object onto the distal end of said fiber.

18. The system of claim 17 wherein the distal optics is a spherical lens.

19. The system of claim 18 wherein the lens includes a circular shoulder and a smaller hemispheric lens extends from the shoulder.

20. The system of claim 15 which comprises:

proximal optics to project the image at the proximal end of the fiber.

21. The system of claim 15 which comprises:

means to illuminate the object to be viewed.

22. The system of claim 15 which includes:

means to scan the multiple cores across an image formed in the image plane to provide sequential viewing of substantially the entire area of the image.

23. The system of claim 22 which comprises:

means to reconstruct and to display the scanned image.

24. The system of claim 23 wherein the means to display is a cathode ray tube.

25. The system of claim 23 wherein the means for reconstruction comprises:

means to scan the proximal and distal ends in synchronism.

26. The system of claim 25 which includes:

third and fourth groups of cores having indices of refractions N₃ and N₄, the indices of refraction of N₃ and N₄ being different from one another and from either of the indices of refraction of the cores N₁ and N₂, the index of refraction being the higher and lower index cores being at least 0.06.

27. The system of claim 25 which includes:

third and fourth groups of cores having indices of refractions N₃ and N₄, the indices of refraction of N₃ and N₄ being different from one another and from either of the indices of refraction of the cores N₁ and N₂, the index of refraction being the higher and lower index cores being at least 0.06.

28. A fiber optic scanning system comprising:

a multifiber having a proximal end and a distal end with a two dimensional array of phase mismatched cores, a first group of cores having an index of refraction N₁ ;

a second group of cores having an index of refraction N₂, the cores being positioned in a matrix;

the cores of the groups being arrayed so that the adjacent cores of any core are members of the other group;

the indices N₁ and N₂ being greater than the index of the surrounding matrix and the index difference between N₁ and N₂ being great enough to produce substantial mismatch in the propagation constants in the cores and to substantially reduce cross talk between any core of one group and any core of the other group;

means to scan the distal end in at least one dimension whereby said core cyclically scans at least a line segment of an image formed in an image plane; and

means to display the scanned image at the proximal end.

29. The system of claim 28 wherein the index difference between N₁ and N₂ is at least about 0.02.

30. The system of claim 28 which comprises:

distal optics to form an image of an object onto the distal end of said multifiber.

31. The system of claim 30 wherein the distal optics is a spherical lens.

32. The system of claim 31 wherein the lens includes a circular shoulder and a smaller hemispheric lens extends from the shoulder.

33. The system of claim 28 which comprises:

means to illuminate the object to be viewed.

34. The system of claim 28 which includes:

means to scan the multiple cores across an image formed in the image plane to provide sequential viewing of substantially the entire area of the image.

35. The system of claim 34 which comprises:

means to reconstruct and to display the scanned image.

36. The system of claim 35 wherein the means to display is a cathode ray tube and the cathode ray scans synchronously in the analogous pattern.

37. The system of claim 35 wherein the means for reconstruction comprises:

means to scan the proximal and distal ends in synchronism.

38. The system of claim 28 which comprises:

means for scanning rotatably about the longitudinal axis of the multifiber.

39. The system of claim 28 which comprises:

proximal optics to project the image at the proximal end of the multifiber.

40. A fiber optic scanning system which comprises:

a multifiber having a proximal end and a distal end having a plurality of cores arrayed in a linear dimension, the cores having different indices of refraction, a first group of cores having an index of refraction N₁ ;

a second group of cores having an index of refraction N₂, the cores being positioned in a matrix;

the cores of the groups being arrayed so that the adjacent cores of any core are members of the other group;

the indices N₁ and N₂ being greater than the index of the surrounding matrix and the index difference between N₁ and N₂ being great enough to produce substantial mismatch in the propagation constants in the cores and to substantially reduce cross talk between any core of one group and any core of the other group;

means to scan the distal end of the cores in at least one dimension whereby said cores cyclically scan at least a line segment of an image formed in an image plane;

means to scan along an orthogonal dimension; and

means to display the scanned image at the proximal end.

41. The system of claim 40 wherein the index difference between N₁ and N₂ is at least about 0.02.

42. The system of claim 40 which comprises:

distal optics to form an image of an object onto the distal end of said multifiber.

43. The system of claim 42 wherein the distal optics is a spherical lens.

44. The system of claim 43 wherein the lens includes a circular shoulder and a smaller hemispheric lends extends from the shoulder.

45. The system of claim 40 which comprises:

proximal optics to project the image at the proximal end of the multifiber.

46. The system of claim 40 which comprises:

means to illuminate the object to be viewed.

47. The system of claim 40 which includes:

means to scan the multiple cores across an image formed on the distal end to provide sequential viewing of substantially the entire area of the image.

48. The system of claim 40 which comprises:

means for reconstructing and displaying the scanned image.

49. The system of claim 48 wherein the means for reconstruction comprises:

means to scan the proximal and distal ends in synchronism.

50. The system of claim 49 wherein the means to display is a cathode ray tube and the cathode ray scans synchronously in the analogous pattern.

51. A fiber optic scanning system comprising:

a multifiber having a proximal end and a distal end with a two dimensional array of cores, the cores having different indices of refraction, a first group of cores having an index of refraction N₁ ;

a second group of cores having an index of refraction N₂, the cores being positioned in a matrix;

the cores of the groups being arrayed so that the adjacent cores of any core are members of the other group;

the indices N₁ and N₂ being greater than the index of the surrounding matrix and the index difference between N₁ and N₂ being great enough to produce substantial mismatch in the propagation constants in the cores and to substantially reduce cross talk between any core of one group and any core of the other group;

means to scan the distal end in one dimension to cyclically scans at least a line segment of an image formed in an image plane; and

means to display the image at the proximal end.

52. The system of claim 51 wherein the index difference between N₁ and N₂ is at least about 0.02.

53. The multifiber of claim 52 which comprises:

distal optics to form an image of an object onto the distal end of said multifiber.

54. The multifiber of claim 53 which comprises:

proximal optics to project the image at the proximal end of the multifiber.

55. The multifiber of claim 54 wherein the distal optics is a spherical lens.

56. The multifiber of claim 55 wherein the lens includes a circular shoulder and a smaller hemispheric lens extends from the shoulder.

57. The multifiber of claim 51 which comprises:

means to illuminate the object to be viewed.

58. The multifiber of claim 51 which includes:

means to scan the multiple cores across an image formed on the distal end to provide sequential viewing of substantially the entire area of the image.

59. The multifiber of claim 58 which comprises:

means for reconstructing and displaying the scanned image.

60. The system of claim 59 wherein the means to display is a cathode ray tube and the cathode ray scans synchronously in the analogous pattern.

61. The multifiber of claim 58 wherein the means for reconstruction comprises:

means to scan the proximal and distal ends in synchronism.