Opto-photo-electric switch

• US 5,130,528 A
• Filed: 03/01/1991
• Issued: 07/14/1992
• Est. Priority Date: 03/01/1991
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Phillips, Alfred Jr.
• Primary Examiner(s): Howell, Janice A.
• Assistant Examiner(s): NGUYEN, KIET TUAN
• Application Number:
  US07/662,689
• Time in Patent Office: 501 Days
• Field of Search: 250/213 A, 250/213 R, 250/211 J, 324/96, 372/107, 359/257
• US Class Current: 250/214.0LS
• CPC Class Codes: G02F 3/00 Optical logic elements; Optical bistable devices
• CPC Class Codes: H03K 17/78 using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled

Abstract

A heterojunction optical switch is taught. Briefly stated, birefringence in the form of a Pockel Cell is utilized such that biasing of the Pockel Cell permits the passage of light therethrough. Preferably, a light detector and resistor are electrically in parallel with the Pockel Cell such that light impinging upon the light detector causes the Pockel Cell to be reverse biased with the result that a separate light source may pass through the Pockel Cell. In this fashion, the Pockel Cell operates as a true optical switch.

Claims

1. An optical switch, comprising:

a Pockel Cell disposed on a semiconductor substrate for permitting the passage of a first light there through in response to an electrical potential applied thereto; and

first biasing means disposed on said semicondutor substrate for applying said electrical potential to said Pockel Cell.

2. The device according to claim 1 wherein said first biasing means is comprised of a light detector for producing said electrical potential in response to the impingement of a second light in the form of optical energy on said light detector.

3. A device according to claim 1 wherein said first biasing means is comprised of one or more devices from the group consisting of:

photodiodes, photocells, and phototransistors.

4. A device according to claim 2 wherein said first biasing means is comprised of one or more light detectors from the group consisting of:

photodiodes, photocells, and phototransistors.

5. The device according to claim 1 wherein said first biasing means is comprised of a power supply.

6. The device according to claim 2 further comprising an impedance means in parallel circuit relationship with said first biasing means.

7. The device according to claim 6 wherein said impedance means is comprised of a resistor.

8. The device according to claim 2 wherein said first biasing means is comprised of at least two light detectors, configured such that said optical energy must impinge upon each of said at least two light detectors, thereby forming a logical AND gate.

9. The device according to claim 2 wherein said light detector is adapted to receive at least two sources of optical energy thereon, such that said light detector produces said electrical potential upon the impingement of optical energy on at least one of said at least two sources of optical energy, thereby forming a logical OR gate.

10. A device according to claim 2 further comprising a second biasing means, said second biasing means operatively connected to said Pockel Cell so as to provide an electrical potential to said Pockel Cell in reverse polarity with respect to said first biasing means and for permitting said passage of said first light through said Pockel Cell, whereby upon said impingement of said optical energy on said light detector, said electrical potential to said Pockel Cell is reduced thereby prohibiting the passage of said first light through said Pockel Cell, thereby form a logical INVERTER gate.

11. A device according to claim 10 wherein said second biasing means is comprised of a voltage source.

12. A device according to claim 10 wherein said second biasing means is comprised of a light detector.

13. A device according to claim 8 further comprising a second biasing means, said second biasing means operatively connected to said Pockel Cell so as to provide an electrical potential to said Pockel Cell in reverse polarity with respect to said first biasing means and for permitting said passage of said first light through said Pockel Cell, whereby upon said impingement of said optical energy on said light detector, said electrical potential to said Pockel Cell is reduced thereby prohibiting the passage of said first light through said Pockel Cell, thereby form a logical NAND gate.

14. A device according to claim 9 further comprising a second biasing means, said second biasing means operatively connected to said Pockel Cell so as to provide an electrical potential to said Pockel Cell in reverse polarity with respect to said first biasing means and for permitting said passage of said first light through said Pockel Cell, whereby upon said impingement of said optical energy on said light detector, said electrical potential to said Pockel Cell is reduced thereby prohibiting the passage of said first light through said Pockel Cell, thereby form a logical NOR gate.

15. A device according to claim 13 wherein said second biasing means is comprised of a light detector.

16. A device according to claim 14 wherein said second biasing means is comprised of a light detector.