Optical switch and gate apparatus and method

• US 20040213508A1
• Filed: 05/25/2004
• Published: 10/28/2004
• Est. Priority Date: 08/22/2002
• Status: Active Grant

• Current Assignee: Main Street Ventures, LLC
• Original Assignee: Main Street Ventures, LLC
• Inventors: Halberthal, Eldan, Shahar, Arle
• Granted Patent: US 7,362,928 B2
• Time in Patent Office: Days
• US Class Current: 385/16
• CPC Class Codes: G02B 2006/12107 Grating
• CPC Class Codes: G02B 2006/12142 Modulator
• CPC Class Codes: G02B 2006/12145 Switch
• CPC Class Codes: G02B 2006/12147 Coupler
• CPC Class Codes: G02B 2006/12164 Multiplexing; Demultiplexing
• CPC Class Codes: G02B 6/04 formed by bundles of fibres G02B6/24 takes precedence
• CPC Class Codes: G02B 6/125 Bends, branchings or intersections
• CPC Class Codes: G02B 6/2746 comprising non-reciprocal devices, e.g. isolators, FRM, circulators, quasi-isolators magneto-optic non-reciprocal devices G02F1/093
• CPC Class Codes: G02B 6/2804 forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers
• CPC Class Codes: G02B 6/2861 using fibre optic delay lines and optical elements associated with them, e.g. for use in signal processing, e.g. filtering delay lines in general H03H, H01P9/00; optical computing devices G06E
• CPC Class Codes: G02B 6/3594 Characterised by additional functional means, e.g. means for variably attenuating or branching or means for switching differently polarized beams
• CPC Class Codes: G02F 1/225 in an optical waveguide structure
• CPC Class Codes: G02F 1/3511 Self-focusing or self-trapping of light; Light-induced birefringence; Induced optical Kerr-effect
• CPC Class Codes: G02F 1/3523 Non-linear absorption changing by light, e.g. bleaching
• CPC Class Codes: H04J 14/02 Wavelength-division multiplex systems
• CPC Class Codes: H04J 14/08 Time-division multiplex systems

Abstract

Some exemplary embodiments of one version of the present invention provide an optical switch including: a splitting device having first, second, third and fourth terminals; a nonlinear element; an attenuator; and an optical loop associated with the third and fourth terminals, the optical loop including the attenuator and the nonlinear element, the nonlinear element being displaced from a mid-point of the optical loop, wherein the splitting device is able to receive an input signal via one of the first and second terminals and an activating signal via one of the first and second terminals and to provide an output signal at one of the first and second terminals in response to the activating signal. In exemplary embodiments of alternative versions of the present inventions, the optical switch may include a threshold device. In some versions, the optical switch may be operated with a continuous wave or a pulse based activating signal.

Claims

1. An optical switch comprising:

a threshold device having first, second and third terminals, said first terminal associated with a nonlinear element and a coupling device for coupling an activating signal from a fourth terminal into said first terminal,

wherein said threshold device is arranged to receive an input signal from said first terminal and to produce an output signal at one of said second and third terminals in response to said activating signal.

2. The switch of claim 1 wherein said threshold device includes an optical loop.

3. The switch of claim 2 wherein said optical loop includes a nonlinear element and an attenuator.

4. The switch of claim 1 wherein said threshold device includes a splitter and a combiner coupled along two optical paths that at least one of said optical paths includes a nonlinear element.

5. The switch of claim 1 wherein said threshold device includes a splitter and a combiner coupled along two optical paths that at least one of said optical paths includes a phase shifter.

6. The switch of claim 1 wherein said first terminal is further arranged to include an isolator.

7. The switch of claim 1 wherein said nonlinear element is further arranged to include an electronic terminal for receiving an electronic activating signal.

8. The switch of claim 7 wherein said threshold device is arranged to produce an output signal at one of said second and third terminals in response to said electronic activating signal.

9. The switch of claim 1 wherein said one of said second and third terminals includes an equalizing device.

10. The switch of claim 9 wherein said equalizing device is selected from a group including attenuators and optical amplifiers.

11. The switch of claim 1 wherein said nonlinear element is selected from a group including semiconductor optical amplifiers and linear optical amplifiers.

12. The switch of claim 1 wherein said coupling device is selected from a group including directional couplers and circulators.

13. The switch of claim 1 comprising at least one optical fiber.

14. The switch of claim 1 comprising at least one planar waveguide.

15. The switch of claim 1 comprising integrated optics.

16. The switch of claim 1 comprising a planar optical circuit.

17. The switch of claim 1 comprising an on-chip optical device.

18. The switch of claim 1 comprising at least in part a gaseous medium or vacuum.

19. The switch of claim 1 wherein said switch includes a portion of a waveguide.

20. The switch of claim 1 wherein said activating signal includes pulses.

21. The switch of claim 1 wherein said activating signal is a continuous wave beam.

22. The switch of claim 1 wherein said activating signal and said input signal have different wavelengths.

23. The switch of claim 1 comprising a wavelength filter.

24. The switch of claim 1 wherein said activating signal and said input signal have the same wavelength.

25. The switch of claim 1 comprising an isolator.

26. An optical switch comprising:

an input and first and second outputs;

first and second signal guiding branches, each branch having first and second terminals, at least one of said first and second branches comprising a non-linear optical element and one of said first and second branches including a coupling device for coupling an activating signal from an activating terminal into one of said first and second branches;

first and second optical couplers, at least one of said first and second optical couplers comprising an asymmetric optical coupler, said first optical coupler configured to split an input signal from said input into a first signal portion propagating through said first branch and a second signal portion propagating through said second branch, said second optical coupler configured to combine said first and second signal portions from said second terminals of said first and second branches, respectively, and to produce an output signal at said one of said first and second outputs in response to said activating signal.

27. The switch of claim 26 wherein said switch includes a symmetric coupler.

28. The switch of claim 26 wherein one of said first and second branches includes a phase shifter.

29. The switch of claim 26 wherein said nonlinear element is further arranged to include an electronic terminal for receiving an electronic activating signal.

30. The switch of claim 29 wherein said non-linear element is arranged to produce an output signal at one of said first and second outputs in response to said electronic activating signal.

31. The switch of claim 26 wherein said one of said second and third terminals includes an equalizing device.

32. The switch of claim 31 wherein said equalizing device is selected from a group including attenuators and optical amplifiers.

33. The switch of claim 26 wherein said nonlinear element is selected from a group including semiconductor optical amplifiers and linear optical amplifiers.

34. The switch of claim 26 wherein said coupling device is selected from a group including directional couplers and circulators.

35. The switch of claim 26 comprising at least one optical fiber.

36. The switch of claim 26 comprising at least one planar waveguide.

37. The switch of claim 26 comprising integrated optics.

38. The switch of claim 26 comprising a planar optical circuit.

39. The switch of claim 26 comprising an on-chip optical device.

40. The switch of claim 26 comprising at least in part a gaseous medium or vacuum.

41. The switch of claim 26 wherein said switch includes a portion of a waveguide.

42. The switch of claim 26 wherein said activating signal includes pulses.

43. The switch of claim 26 wherein said activating signal is a continuous wave beam.

44. The switch of claim 26 wherein said activating signal and said input signal have different wavelengths.

45. The switch of claim 26 comprising a wavelength filter.

46. The switch of claim 26 wherein said activating signal and said input signal have the same wavelength.

47. The switch of claim 26 comprising an isolator.

48. An optical switch comprising:

a splitting device having first second third and fourth terminals;

a nonlinear element;

an attenuator; and

an optical loop associated with said third and fourth terminals, said optical loop including said attenuator and said nonlinear element, said nonlinear element being displaced from a mid-point of said optical loop,

wherein said splitting device is able to receive an input signal via one of said first and second terminals and an activating signal via one of said first and second terminals, and to provide an output signal at one of said first and second terminals in response to said activating signal.

49. The switch of claim 48 wherein said at least one of said first and second terminal includes a coupling device for coupling an activating signal from an activating terminal into one of said first and second terminals.

50. The switch of claim 48 wherein said optical loop is arranged to further include a coupling device for coupling a second activating signal into said nonlinear element.

51. The switch of claim 48 wherein said splitting device is a symmetric coupler.

52. The switch of claim 48 wherein said nonlinear element is further arranged to include an electronic terminal for receiving an electronic activating signal.

53. The switch of claim 52 wherein said non-linear element is arranged to produce an output signal at one of said first and second outputs in response to said electronic activating signal.

54. The switch of claim 48 wherein said nonlinear element is selected from a group including semiconductor optical amplifiers and linear optical amplifiers.

55. The switch of claim 48 wherein said coupling device is selected from a group including directional couplers and circulators.

56. The switch of claim 48 comprising at least one optical fiber.

57. The switch of claim 48 comprising at least one planar waveguide.

58. The switch of claim 48 comprising integrated optics.

59. The switch of claim 48 comprising a planar optical circuit.

60. The switch of claim 48 comprising an on-chip optical device.

61. The switch of claim 48 comprising at least in part a gaseous medium or vacuum.

62. The switch of claim 48 wherein said switch includes a portion of a waveguide.

63. The switch of claim 48 wherein said activating signal includes pulses.

64. The switch of claim 48 wherein said activating signal is a continuous wave beam.

65. The switch of claim 48 wherein said attenuator is selected from a group including optical amplifiers and couplers.

66. The switch of claim 48 wherein said one of said second and third terminals includes an equalizing device.

67. The switch of claim 66 wherein said equalizing device is selected from a group including attenuators and optical amplifiers

68. The switch of claim 48 wherein said activating signal and said input signal have different wavelengths.

69. The switch of claim 48 comprising a wavelength filter.

70. The switch of claim 48 wherein said activating signal and said input signal have the same wavelength.

71. The switch of claim 48 comprising an isolator.

72. An optical switch comprising:

a splitting device having first, second, third and fourth terminals;

a nonlinear element;

a coupling device; and

an optical loop associated with said third and fourth terminals, said optical loop including said nonlinear element, displaced from a mid-point of said optical loop, and said coupling device, which is able to produce loss in said optical loop and to couple a continuous wave activating signal from an activating terminal into said nonlinear element,

wherein said splitting device is arranged to receive an input signal via one of said first and second terminals and to provide an output signal at one of said first and second terminals in response to said continuous wave activating signal.

73. The switch of claim 72 wherein one of said first and second terminals are further arranged to include a coupling device for coupling said output signal from one of said first and second terminals into a fifth terminal.

74. The switch of claim 72 wherein said optical loop includes an attenuator.

75. The switch of claim 74 wherein said attenuator is selected from a group including optical amplifiers and couplers.

76. The switch of claim 72 wherein said optical loop is arranged to further include a coupling device for coupling a second activating signal into said nonlinear element.

77. The switch of claim 72 wherein said splitting device is a symmetric coupler.

78. The switch of claim 72 wherein said nonlinear element is further arranged to include an electronic terminal for receiving an electronic activating signal.

79. The switch of claim 78 wherein said non-linear element is arranged to produce an output signal at one of said first and second outputs in response to said electronic activating signal.

80. The switch of claim 72 wherein said nonlinear element is selected from a group including semiconductor optical amplifiers and linear optical amplifiers.

81. The switch of claim 72 wherein said coupling device is selected from a group including directional couplers and circulators.

82. The switch of claim 72 comprising at least one optical fiber.

83. The switch of claim 72 comprising at least one planar waveguide.

84. The switch of claim 72 comprising integrated optics.

85. The switch of claim 72 comprising a planar optical circuit.

86. The switch of claim 72 comprising an on-chip optical device.

87. The switch of claim 72 comprising at least in part a gaseous medium or vacuum.

88. The switch of claim 72 wherein said switch includes a portion of a waveguide.

89. The switch of claim 72 wherein said attenuator is selected from a group including optical amplifiers and couplers.

90. The switch of claim 72 wherein said one of said second and third terminals includes an equalizing device.

91. The switch of claim 90 wherein said equalizing device is selected from a group including attenuators and optical amplifiers

92. The switch of claim 72 wherein said activating signal and said input signal have different wavelengths.

93. The switch of claim 72 comprising a wavelength filter.

94. The switch of claim 72 wherein said activating signal and said input signal have the same wavelength.

95. The switch of claim 72 comprising an isolator.