Method and apparatus for forming erasable, real time, optical circuits

• US 3,993,400 A
• Filed: 02/14/1975
• Issued: 11/23/1976
• Est. Priority Date: 02/14/1975
• Status: Expired due to Term

• Current Assignee: Grumman Aerospace Corporation (Northrop Grumman Corporation)
• Original Assignee: Grumman Aerospace Corporation (Northrop Grumman Corporation)
• Inventors: Leib, Kenneth G.
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): DELOS Reyes, B. Wm.
• Application Number:
  US05/550,040
• Time in Patent Office: 648 Days
• Field of Search: 350/96 BC, 350/96 C, 350/96 B, 350/96 WG, 350/320, 350/160 L, 350/160 LC
• US Class Current: 385/73
• CPC Class Codes: G02F 1/0533 structurally associated with a photo-conductive layer
• CPC Class Codes: G02F 1/1313 specially adapted for a particular application
• CPC Class Codes: G02F 1/1326 Liquid crystal optical waveguides or liquid crystal cells specially adapted for gating or modulating between optical waveguides
• CPC Class Codes: G02F 1/135 Liquid crystal cells structurally associated with a photoconducting or a ferro-electric layer, the properties of which can be optically or electrically varied G02F1/133348 takes precedence
• CPC Class Codes: G02F 1/313 in an optical waveguide structure

Abstract

A method and apparatus for forming optical circuit channels and components in a transducer for connecting optical elements coupled to the transducer including the steps of and associated apparatus for, generating a light beam, directing the light beam toward the transducer, controlling the transmission of the light beam to expose a predetermined portion of the transducer to the light beam in accordance with a predetermined pattern, optically coupling certain optical elements of the transducer in accordance with the predetermined circuit pattern formed in the transducer by the light beam, and erasing the optical pattern formed in the transducer.

Claims

1. A method of providing real time optical channels and components for interconnecting optical fibers coupled to a transducer, comprising the steps of:

coupling the optical fibers to the transducer to provide an air free connection between the optical fibers and the transducer;

generating the light beam;

directing the light beam toward the transducer;

controlling the transmission of the light beam to expose a predetermined portion of the transducer in accordance with a perdetermined pattern;

optically interconnecting the optical fibers in accordance with the predetermined pattern upon exposure of the transducer to the light beam; and

subsequently erasing the optical interconnection between the optical fibers.

2. The method recited in claim 1 including the step of:

changing the predetermined pattern after the erasure step to provide optical interconnection of the optical elements in accordance with the changed pattern.

3. The method recited in claim 1 including the step of:

varying the index of refraction of curved optical interconnections in accordance with a parabolic distribution to minimize radiation losses.

4. The method recited in claim 1 including the step of:

filtering and focussing the generated light.

5. The method recited in claim 1 including the step of:

directing the light beam through a film having the predetermined pattern.

6. The method recited in claim 5 including the step of:

re-focussing the light beam emanating from the film.

7. The method recited in claim 1 including the step of:

directing the generated light beam onto the transducer at an angle of 90°

to the plane of the transducer.

8. The method recited in claim 1 including the step of:

aligning the light beam, predetermined pattern, and transducer.

9. The method recited in claim 1 wherein the step of controlling the transmission includes the step of:

deflecting the light beam onto the transducer in accordance with X-Y coordinate related drive signals.

10. The method recited in claim 9 including the step of:

varying the linewidth of the deflected light beam.

11. The method recited in claim 1 including the step of:

connecting poling electrodes to the transducer to optimize the optical pattern generated therin upon exposure to the light beam.

12. The method recited in claim 1 including the step of:

incorporating lumpted optical components within the transducer.

13. The method recited in claim 1 including the step of:

biasing the transducer for operation in the birefringent mode to optimize the conditions for providing an optical pattern in the transducer upon exposure to the generated light beam.

14. The method recited in claim 1 including the step of:

biasing the transducer for operation in the dynamic scattering mode.

41. The system according to claim 3 wherein the step of generating a light beam is performed using a laser.

15. A system for providing real time optical channels and components for optical fibers coupled to a transducer, comprising:

optical fibers mechanically coupled to the transducer through connectors extending outwardly therefrom, said connectors including means for expelling air to provide an air-free coupling between the optical fibers and the transducer upon insertion of the optical fibers into the connectors;

means for generating a light beam;

means interposed between said generating means and the transducer for transmitting a predetermined portion of the light beam to the transducer in accordance with a predetermined optical pattern to interconnect the optical fibers in accordance with the predetermined optical pattern formed in the transducer; and

means for erasing the optical pattern formed in the transducer.

16. The system recited in claim 15 wherein:

the transducer includes a photoconductive layer and an optical layer, sandwiched between a pair of transparent electrode layers.

17. The system recited in claim 16 wherein:

said optical layer is a nematic liquid crystal.

18. The system recited in claim 16 wherein:

said optical layer is a ferroelectric ceramic.

19. The system recited in claim 16 wherein:

said photoconductive layer includes cadmium sulfide and said transparent electrode layers include glass.

20. The system recited in claim 15 wherein:

said generating means includes a laser.

21. The system recited in claim 15 wherein:

said generating means includes an argon laser.

22. The system recited in claim 15 wherein:

said generating means includes a light emitting diode.

23. The system recited in claim 15 wherein:

said generating means includes an injection laser.

24. The system recited in claim 15 wherein:

said transmitting means includes a plurality of patterns.

25. The system recited in claim 15 including:

means for filtering and focussing the generated light beam.

26. The system recited in claim 25 including:

means for re-focussing the light beam upon exiting from said transmitting means.

27. The system recited in claim 15 wherein:

said transmitting means includes a mask having a glass substrate and copper coating on one side thereof, the optical pattern corresponding to the removed portions of the copper coating.

28. The system recited in claim 15 wherein:

said transmitting means includes a film.

29. The system recited in claim 15 wherein:

said generating means includes a laser;

said transmitting means includes a laser scanner with drive means for establishing X and Y coordinates and providing an output beam pattern in response to the generated laser beam.

30. The system recited in claim 29 wherein:

said laser scanner includes a lens, the linewidth of the output beam is equal to 1.27 (λ

/a)

f where λ

, a, and f are the wavelength and radius of the generated laser beam and f is the focal length of the lens.

31. The system recited in claim 15 wherein:

the transducer is oriented perpendicular to the light beam emanating from said generating means.

32. The system recited in claim 15 wherein:

the transducer has poling electrodes coupled thereto.

33. The system recited in claim 15 wherein:

the transducer includes a ferroelectric ceramic.

34. The system recited in claim 15 wherein:

the transducer includes a nematic liquid crystal with lumped components embedded therein.

35. The system recited in claim 34 wherein:

said lumped components include an injection laser.

36. The system recited in claim 15 wherein:

the transducer includes a photoconductive layer affixed to a ferroelectric ceramic layer with a plurality of transparent electrode strips arranged on the exposed sides of said layers.

37. The system recited in claim 15 including:

39. The system recited in claim 15 including:

voltage means for biasing the transducer for operation in the dynamic scattering mode.

40. The system recited in claim 15 including:

voltage means for biasing the transducer for operation in the birefringement and dynamic scattering mode.

42. The system according to claim 24 wherein said generating means includes a laser.

38. voltage means for biasing the transducer for operation in the birefringent mode.