Self-aligning optical transceiver

• US 5,347,387 A
• Filed: 03/24/1992
• Issued: 09/13/1994
• Est. Priority Date: 03/24/1992
• Status: Expired due to Fees

• Current Assignee: Robert C. Rice
• Original Assignee: Robert C. Rice
• Inventors: Rice, Robert C.
• Primary Examiner(s): Chilcot, Jr., Richard E.
• Assistant Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US07/856,995
• Time in Patent Office: 903 Days
• Field of Search: 359/143, 359/144, 359/152-153, 359/159, 359/169-170, 250/203.2, 356/5, 356/152, 318/640
• US Class Current: 398/129
• CPC Class Codes: H04B 10/1125 using a single common optical path

Abstract

A compact self-aligning transceiver for high bandwidth cooperative duplex communications, laser image projections or surveillance applications comprises a base mounted hermetic transparent sphere encapsulating a system of two or more pancake motors, two of which are being nested and orthogonal to each other to suspend and rotate a system of optical components centrally located within said motors for receiving and selectively transmitting radiation beams.

Claims

1. A compact transceiver adapted for carrier mounting to optically span free space, atmosphere or underwater for laser image projection comprising:

a spherical radiation permeable shell having a supporting base for hermetically housing components thereof;

(a) a system of motors including two nested pancake motors;

an outer motor having its stator supported by the shell and an inner motor having its stator supported within and orthogonal to an outer motor armature, outer and inner armatures of said pancake motors being suspended in a frictionless manner from their respective stators and having some lateral and rotational freedom of movement so as to isolate the armatures from the stator movement;

(b) said armatures having a common center clearance for a telescope to expand and collimate transmission radiation, focus received radiation and to reflect and absorb off-axis radiation;

said telescope being coaxially mounted on a platform which is transversely supported by the inner motor armature within said clearance;

(c) means, responsive to modulated transmission radiation containing information from the carrier for generating an intense coherent radiation to be expanded and collimated by said telescope; and

phase proportional logic means selected from the group consisting of internal and external to the shell for effecting said system of motors to direct said telescope to a pre-determined direction relative to the carrier mounting whereby said transmission radiation is maintained in the desired direction and isolated from carrier movement.

4. The transceiver in accordance with claims 1, 2 and 3 wherein means for generating coherent radiation is a laser diode.

5. A transceiver according to claim 4 wherein the telescope comprising an off-axis paraboloidal mirror in optical communication with the laser diode for collimating the transmission radiation;

a concave paraboloidal object mirror having a center opening, co-axially mounted on the platform for expanding and compressing radiation; and

a convex paraboloidal mirror disposed above said object mirror for reflecting radiation.

6. The transceiver in accordance with claim 5 wherein said concave object mirror is made of laminated piezo-ceramic material with silver electroplated segments to enable mutating the shape of the mirror to compensate for environmental aberrations.

7. The transceiver in accordance with claims 1, 2 or 3 further comprising means for cooling said housed components, said means including a closed mechanical refrigeration system having refrigerant in fluid communication with the interior of said shell, said system including a compressor, motor, evaporator and condenser.

8. The transceiver in accordance with claim 7 wherein said condenser is partially embedded in said shell-thus providing heat to the shell.

9. The transceiver in accordance with claim 7 wherein said compressor is contained within said supporting base and wherein said system of motors includes a mechanical transmission driven by the compressor motor for rotating said outer pancake motor stator within said shell.

17. The transceiver of claims 1, 2 or 3 wherein said system of motors further comprising a base motor for rotating the shell, thereby rotating the outer pancake motor stator;

each motor of said system having means for generating torque between its stator and armature;

each pancake motor having a circular, flat armature fabricated of Printed Circuit Board (PCB) with an interlace of phase windings near it edge; and

each pancake motor stator consisting of two flat rings, said rings being spaced from and fixed to each other and straddling over its armature edge and at a clearance therefrom; and

each pancake motor having means for frictionlessly suspending the armature from its stator thereby isolating the armature from vibration of its stator transmitted to it from the carrier.

18. The transceiver in accordance with claim 17 wherein said base motor is within the shell and pivots on the outer pancake motor stator.

19. The transceiver in accordance with claim 17 wherein the supporting base provides a flexible shaft in fluid communication with the shell;

and the base motor rotates said shaft thereby pivoting the shell wherein the outer motor stator is affixed to the inside of the shell and the axis of the outer motor is orthogonal to the flexible shaft.

20. The transceiver in accordance with claim 17 wherein the inner motor armature moves approximately -30 degree from its displacement;

the outer pancake motor armature moves greater than -90 degree but less than -180 degree from its displacement;

the base motor armature moves approximately 360 degree; and

the motors having means for encoding angular displacements of their armatures relative to their stators.

21. The transceiver in accordance with claim 17 wherein said means for generating torque comprises offset multiple phase windings over the armature and said stator flat rings are zig-zag shaped and having inner and outer diameters generally conforming to the shape of the armature phase windings with some windings partially covered.

22. The transceiver in accordance with claim 17 wherein means for generating torque further comprises:

permanent magnets within the stators for generating static magnetic fields permeating the edges of the armatures at intervals and

the phase windings of the armatures being in spiral patterns for generating torque.

23. The transceiver in accordance with claim 17 wherein said frictionless suspension means for each pancake motor armature from its stator is electromagnetic and effected by currents in pancake motor armature phase windings and wherein

said armature has a magnetic center layer magnetically isolates said phase windings on both sides of said center layer thereby actively centering the armature between its stator rings by currents in said phase windings;

said armatures further comprises copper lands etched in a cover layer on both sides of the PCB, each forming a variable capacitor with the stator ring, said variable capacitors collectively detecting an off-center condition; and

said electromagnetic armature suspension further enables measurement of forces acting on the armature.

24. The transceiver in accordance with claim 17 further comprising means for directly cooling said pancake motor armatures, said cooling means being refrigerant evaporation within the PCB and wherein said frictionless suspension for said armatures from said stators is effected by pneumatic pressure from said vaporized refrigerant exhausting from a plurality of ports around both sides of the armature edges.

2. A compact transceiver adapted for carrier mounting to electromagnetically span free space, atmosphere or underwater for surveillance of surrounding objects comprising:

a spherical radiation permeable shell having a supporting base for hermetically housing components thereof;

(a) a system of motors including two nested pancake motors;

an outer motor having its stator supported by the shell and an inner motor having its stator supported within and orthogonal to an outer motor armature, outer and inner armatures of said pancake motors being suspended in a frictionless manner from their respective stators and having some lateral and rotational freedom of movement so as to isolate the armatures from stator movement;

(b) said armatures having a center clearance for a telescope to expand and collimate transmission radiation, focus received radiation and to reflect and absorb off-axis radiation;

said telescope being coaxially mounted on a platform which in turn is transversely supported by the inner motor armature;

(c) means, responsive to modulated transmission radiation containing information from the carrier for generating an intense coherent radiation to be expanded and collimated by said telescope;

(d) means mounted on said platform for separating a received radiation from the transmission radiation, said received radiation being a portion of the transmission radiation reflected back from the surrounding objects;

(e) means for determining the distance to the surrounding reflecting objects including means for measurement of time delay between transmission and receipt of reflected radiation; and

phase proportional logic means selected from the group consisting of internal and external to the shell for effecting said system of motors to direct said telescope to a pre-determined direction relative to the carrier mounting whereby said transmission radiation is maintained in the desired direction and isolated from carrier movement.

10. The transceiver in accordance with claims 2 or 3 wherein said means for focusing the separated received radiation to the photo-detecting device is an off-axis paraboloidal converging mirror in optical communication with said separated received radiation.

11. The transceiver in accordance with claims 2 or 3 further comprising means for rejecting extraneous radiation said means being a molded plastic housing.

13. The transceiver in accordance with claims 2 or 3 wherein said means for separating the received radiation from the transmission radiation is a polarizing beam splitter in optical communication with said radiations.

14. The transceiver of claim 13 further comprising a retardation plate, in optical communication with said beam splitter and interposed within said telescope for rotating the polarization of the transmission and received radiation relative to the beam splitter and said retardation plate being selected from the group consisting of a half and a quarter wave retarder.

15. The transceiver in accordance with claim 14 further comprising means to rotate said retardation plate for effectively varying the degree of rotation of said radiation polarization.

16. The transceiver in accordance with claim 15 wherein means to rotate said retardation plate is a third pancake motor coaxial to the telescope and said motor supports the retardation plate.

3. A compact transceiver adapted for carrier mounting to electromagnetically span free space, atmosphere or underwater for telecommunication of information with a cooperating device comprising:

a spherical radiation permeable shell having a supporting base for hermetically housing components thereof;

(a) a system of motors including two nested pancake motors;

an outer motor having its stator supported by the shell and an inner motors having its stator supported within and orthogonal to an outer motor armature, outer and inner armatures of said pancake motors being suspended in a frictionless manner from their respective stators and having some lateral and rotational freedom of movement so as to isolate the armature from the stator movement;

(b) said armature having a center clearance for a telescope to expand and collimate transmission radiation, focus received radiation and to reflect and absorb off-axis radiation;

said telescope being supported by a platform which in turn is transversely supported by the inner motor armature;

(c) means, responsive to modulated transmission radiation containing information from the carrier for generating an intense coherent radiation to be expanded and collimated by said telescope;

(d) means mounted on said platform for separating a received radiation from the transmission radiation, and focusing said received radiation to a detecting device, said received radiation being transmitted from a cooperating device;

(e) means for determing the direction of said received radiation relative to said transmission radiation so as to track said cooperating device;

(f) means for encoding and decoding information for modulated transmission radiation and for modulated received radiation respectively; and

phase proportional logic means selected from the group consisting of internal and external to the shell for effecting said system of motors to direct said telescope to a pre-determined direction relative to the carrier mounting whereby said transmission radiation is maintained in the desired direction and isolated from carrier movement.

12. The transceiver in accordance with claim 3, further comprising at least one intensity-modulated radiation emitting diode for signaling the cooperating device.

25. The transceiver in accordance with claim 3 wherein said tracking means is a photo-detecting device having at least three proportional outputs thereby causing the logic means to determine the direction of the received radiation relative to the transmission radiation;

withdrawal of rejections and reexamination of the amended claims are requested.

26. The transceiver in accordance with claim 3 wherein said means for tracking the cooperating device is a translation motor responsive to the logic means to move the detecting device in a desired direction relative to said focusing means thereby enabling the logic means to determine the direction of the received radiation relative to the transmission radiation and further enabling the logic means to protect the detecting device from intense radiation by moving the device behind a baffle within a plastic housing.