Modulated light source

• US 20040017963A1
• Filed: 04/08/2003
• Published: 01/29/2004
• Est. Priority Date: 05/17/1999
• Status: Active Grant

• Current Assignee: AL Cielo Ltd.
• Original Assignee: Chiaro Networks, Ltd.
• Inventors: Shekel, Eyal
• Granted Patent: US 6,917,725 B2
• Time in Patent Office: Days
• US Class Current: 385/14
• CPC Class Codes: G02B 6/4204 the coupling comprising intermediate optical elements, e.g. lenses, holograms encapsulated active devices H01S5/02208, H01L33/52
• CPC Class Codes: G02F 1/3136 of interferometric switch type

Abstract

A method of producing a modulated light source including the steps of providing a modulator, fiberlessly coupling a laser diode light source to the modulator and enclosing the modulator and the laser diode light source within a housing together with output optics operative to direct modulated light from the modulator into an optical fiber extending outwardly from the housing.

Claims

1. A modulated light source module comprising:

a modulator disposed in a housing;

a laser diode light source disposed in said housing and fiberlessly coupled to said modulator; and

output optics operative to direct modulated light from the modulator into an optical fiber extending outwardly from said housing.

2. A modulated light source according to claim 1 and wherein said modulator comprises:

an input multi-mode interference coupler;

an output multi-mode interference coupler; and

first and second waveguides interconnecting said input multi-mode interference coupler and said output multi-mode interference coupler, said first and second waveguides having associated therewith electrodes for the application of voltage thereacross, thereby to vary the phase of light passing therealong.

3. A modulated light source according to claim 1 and wherein said modulator comprises:

an input Y-junction splitter;

an output Y-junction combiner; and

first and second waveguides interconnecting said Y-junction splitter and said output Y-junction combiner, said first and second waveguides having associated therewith electrodes for the application of voltage thereacross, thereby to vary the phase of light passing therealong.

4. A modulated light source according to claim 1 and wherein said laser diode light source is monolithically integrated with said modulator.

5. A modulated light source according to claim 4 and wherein said laser diode light source is monolithically integrated with said modulator and occupy different regions of at least some of identical epitaxial layers.

6. A modulated light source according to claim 1 and wherein said laser diode light source is a discrete element which is mechanically mounted in a desired position with respect to said modulator.

7. A modulated light source according to claim 6 and wherein said laser diode light source is butted against an input to said modulator.

8. A modulated light source according to claim 6 and wherein said laser diode light source is coupled to an input to said modulator via a discrete lens.

9. A modulated light source according to claim 8 and wherein each of said laser diode light source and said modulator are mounted on parallel surface mountings, said parallel surface mountings include mutually facing surfaces which lie in parallel planes which are perpendicular to an optical axis of a light beam propagating from said laser diode light source towards said modulator via said lens.

10. A modulated light source according to claim 9 and wherein said laser diode light source and said modulator are aligned by relative movement thereof in said parallel planes and are fixed in desired alignment by fixing said mutually facing surfaces together.

11. A modulated light source according to claim 6 and wherein at least one of said laser diode light source and said modulator are mounted onto a support element by means of side mounting blocks which are fixed in position upon precise mutual alignment of said laser diode light source and said modulator.

12. A modulated light source according to claim 7 and wherein at least one of said laser diode light source and said modulator are mounted onto a support element by means of side mounting blocks which are fixed in position upon precise mutual alignment of said laser diode light source and said modulator.

13. A modulated light source according to claim 8 and wherein at least one of said laser diode light source and said modulator are mounted onto a support element by means of side mounting blocks which are fixed in position upon precise mutual alignment of said laser diode light source and said modulator.

14. A modulated light source according to claim 1 and wherein said modulator is implemented in gallium arsenide.

15. A modulated light source according to claim 14 and wherein said modulator comprises:

an input multi-mode interference coupler;

an output multi-mode interference coupler; and

first and second waveguides interconnecting said input multi-mode interference coupler and said output multi-mode interference coupler, said first and second waveguides having associated therewith electrodes for the application of voltage thereacross, thereby to vary the phase of light passing therealong.

16. A modulated light source according to claim 14 and wherein said modulator comprises:

an input Y-junction splitter;

an output Y-junction combiner; and

first and second waveguides interconnecting said Y-junction splitter and said output Y-junction combiner, said first and second waveguides having associated therewith electrodes for the application of voltage thereacross, thereby to vary the phase of light passing therealong.

17. A modulated light source according to claim 14 and wherein said laser diode light source is monolithically integrated with said modulator.

18. A modulated light source according to claim 17 and wherein said laser diode light source is monolithically integrated with said modulator and occupy different regions of at least some of identical epitaxial layers.

19. A modulated light source according to claim 14 and wherein said laser diode light source is a discrete element which is mechanically mounted in a desired position with respect to said modulator.

20. A modulated light source according to claim 19 and wherein said laser diode light source is butted against an input to said modulator.

21. A modulated light source according to claim 19 and wherein said laser diode light source is coupled to an input to said modulator via a discrete lens.

22. A modulated light source according to claim 21 and wherein each of said laser diode light source and said modulator are mounted on parallel surface mountings, said parallel surface mountings include mutually facing surfaces which lie in parallel planes which are perpendicular to an optical axis of a light beam propagating from said laser diode light source towards said modulator via said lens.

23. A modulated light source according to claim 22 and wherein said laser diode light source and said modulator are aligned by relative movement thereof in said parallel planes and are fixed in desired alignment by fixing said mutually facing surfaces together.

24. A modulated light source according to claim 19 and wherein at least one of said laser diode light source and said modulator are mounted onto a support element by means of side mounting blocks which are fixed in position upon precise mutual alignment of said laser diode light source and said modulator.

25. A modulated light source according to claim 20 and wherein at least one of said laser diode light source and said modulator are mounted onto a support element by means of side mounting blocks which are fixed in position upon precise mutual alignment of said laser diode light source and said modulator.

26. A modulated light source according to claim 21 and wherein at least one of said laser diode light source and said modulator are mounted onto a support element by means of side mounting blocks which are fixed in position upon precise mutual alignment of said laser diode light source and said modulator.

27. A method of producing a modulated light source comprising the steps of:

providing a modulator;

fiberlessly coupling a laser diode light source to said modulator; and

enclosing said modulator and said laser diode light source within a housing together with output optics operative to direct modulated light from the modulator into an optical fiber extending outwardly from said housing.

28. A method of producing a modulated light source according to claim 27 and wherein the step of fiberlessly coupling a laser diode light source to said modulator comprises the steps of:

using at least one external manipulator, manipulating at least one of the modulator and the laser diode light source relative to the other such that the output beam of said laser diode enters the modulator with relatively low light loss; and

fixing the modulator and the laser diode light source in desired relative positions independently of the external manipulator; and

disengaging the at least one external manipulator from the modulated light source.

29. A method according to claim 28 and wherein the step of fixing the modulator and the laser diode light source in desired relative positions comprises fixedly attaching parallel surfaces attached to said modulator and to said laser diode light source to each other in desired relative orientations.

30. A method according to claim 28 and wherein the step of fixing the modulator and the laser diode light source in desired relative positions comprises employing side mounting blocks to fix at least one of said laser diode light source and said modulator in position upon precise mutual alignment of said laser diode light source and said modulator.