Method and apparatus for steering light

• US 5,392,151 A
• Filed: 06/28/1994
• Issued: 02/21/1995
• Est. Priority Date: 12/23/1991
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Nelson, William E.
• Primary Examiner(s): Ben, Loha
• Assistant Examiner(s): Phan, James
• Application Number:
  US08/267,321
• Time in Patent Office: 238 Days
• Field of Search: 359/196-199, 359/212-214, 359/220, 359/223-226, 359/230, 359/234, 359/299, 359/302, 359/201, 359/846, 359/847, 359/900, 358/474, 348/203
• US Class Current: 359/223.1
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field

Abstract

The method disclosed comprises the steps of directing light to a plurality of modulators where each modulator comprises a mirror rotatably fixed to at least two support members displaced from all outer edges of the mirror and an electrode for rotating the mirror, selecting an angle through which the mirror is to rotate, generating a signal characteristic of the angle, applying the characteristic signal to the electrode, and rotating the mirror through the selected angle.

Claims

1. A method of steering light, comprising the steps of:

directing light to a plurality of modulators, each modulator comprising a mirror rotatably fixed to at least two support members displaced from all outer edges of the mirror and an electrode for rotating said mirror;

selecting an angle through which the mirror is to rotate;

generating a signal characteristic of the angle through which the mirror is to rotate;

applying said characteristic signal to the electrode; and

rotating the mirror through the selected angle.

2. The method of claim 1 further comprising the steps of collimating the light to form a collimated light beam.

3. The method of claim 1 wherein the characteristic signal is a periodic voltage.

4. The method of claim 3 wherein the characteristic signal is a periodic voltage allowing the modulator to simulate a one dimensional optical surface.

5. The method of claim 3 wherein the characteristic signal comprises a first and a second voltages.

6. The method of claim 5 wherein the first and second voltages allow the modulator to model a one dimensional optical surface.

7. The method of claim 1 wherein the characteristic signal is equal to a resonant frequency of the modulator.

8. The method of claim 1 wherein the characteristic signal models a one dimensional optical surface.

9. An apparatus for steering light comprising:

a light source;

a plurality of modulators, each of said modulators having a deflector and a mirror rotatably fixed to at least two support members axially aligned along a length of said mirror, wherein said at least two support members are displaced from all outer edges of said mirror, forming the axis of rotation; and

electronic circuitry for generating a signal characteristic of an angle through which the mirror is to be deflected and for applying the signal to the modulator.

10. The apparatus of claim 9 wherein the light source further comprises a collimator for producing a collimated light beam.

11. The apparatus of claim 9 wherein the light source is a laser.

12. The apparatus of claim 9 wherein the plurality of modulators are formed on a single substrate.

13. The apparatus of claim 9 wherein the deflector is an electrode.

14. The apparatus of claim 9 wherein the deflector comprises a pair of electrodes disposed along a line perpendicular to the axis of rotation.

15. The apparatus of claim 9 further comprising a stop for preventing the mirror from contacting the deflector.

16. An apparatus for steering light comprising:

a light source;

a plurality of modulators, each modulator having a deflector and a mirror rotatably fixed to at least two support members axially aligned along a length of said mirror, wherein said at least two support members are displaced from all outer edges of said mirror; and

electronic circuitry for generating control signals characteristic of angles through which each mirror is to rotate, and for applying the control signals to the modulator.

17. The apparatus of claim 16 wherein the modulators are formed on a single substrate.

18. The apparatus of claim 16 wherein the deflector comprises an electrode.

19. The apparatus of claim 16 wherein the deflector comprises an electrode pair disposed along a line perpendicular to the line formed by the at least two support members.