Methods and apparatus for increasing efficiency and optical bandwidth of a microelectromechanical system piston-mode spatial light modulator

Patent metadata

Field	Value
Publication number	US-10831018-B2
Application number	US-201715836521-A
Country	US
Kind code	B2
Filing date	Dec 8, 2017
Priority date	Dec 8, 2017
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

In methods and apparatus for increasing efficiency and optical bandwidth of a microelectromechanical system piston-mode spatial light modulator, an example apparatus includes: an electrode with spring legs; a base electrode; a mirror displacement determiner to determine a periodic signal corresponding to a displacement distance of the electrode beyond an instability point of the electrode; and a voltage source to output a periodic voltage to the base electrode in response to the periodic signal. The periodic voltage causes the spring legs to vary displacement of the electrode with respect to the base electrode according to the periodic voltage. The displacement includes distances beyond the instability point.

First claim

What is claimed is:

1. Apparatus to increase displacement of a mirror in a microelectromechanical system piston-mode spatial light modulator, the apparatus comprising:
an electrode with spring legs;
a base electrode;
a receiver configured to receive an instruction to displace the electrode by a displacement distance;
a mirror displacement determiner coupled to the receiver and configured to determine that the displacement distance is beyond an instability point of the electrode and to determine a periodic signal corresponding to the displacement distance; and
a voltage source to output a periodic voltage to the base electrode in response to the periodic signal, the periodic voltage to cause the spring legs to vary displacement of the electrode with respect to the base electrode according to the periodic voltage, the displacement including distances beyond the instability point.

2. The apparatus of claim 1 , further including a transmitter to transmit at least one of periodic voltage data or sampling data to a receiving device.

3. The apparatus of claim 1 , wherein the periodic voltage is to allow the electrode to displace beyond the instability point without collapsing.

4. The apparatus of claim 1 , wherein the periodic voltage is at least one of a digital pulsing signal or a sinusoid.

5. The apparatus of claim 1 , wherein, when the instruction is for a displacement distance that is less than the instability point of the electrode:
the mirror displacement determiner is to determine a stable signal corresponding to the displacement distance; and
in response to the stable signal, the voltage source is to output a stable voltage to the base electrode to cause the spring legs to displace the electrode to the displacement distance.

6. The apparatus of claim 1 , wherein the electrode is coupled to the mirror.

7. A method to increase displacement of a mirror in a microelectromechanical system piston-mode spatial light modulator, the method comprising:
determining a periodic signal corresponding to a displacement distance of an electrode of a pixel beyond an instability point of the electrode; and
outputting a periodic voltage to a base electrode in response to the periodic signal, the periodic voltage causing spring legs of the electrode to vary displacement of the electrode with respect to the base electrode according to the periodic voltage, the displacement including distances beyond the instability point.

8. The method of claim 7 , further including transmitting at least one of periodic voltage data or sampling data to a receiving device.

9. The method of claim 7 , wherein outputting the periodic voltage allows the spring legs to displace the electrode beyond the instability point without collapsing.

10. The method of claim 7 , wherein the periodic voltage is at least one of a digital pulsing signal or a sinusoid.

11. The method of claim 7 , further including:
when the displacement distance is less than the instability point of the electrode: determining a stable signal corresponding to the displacement distance; and, in response to the stable signal, outputting a stable voltage to the base electrode to cause the spring legs to displace the electrode to the displacement distance.

12. The method of claim 7 , wherein the electrode is coupled to the mirror.

13. A non-transitory computer-readable medium storing instructions that are processable by an instruction execution apparatus for causing the apparatus to perform a method comprising:
determining a periodic signal corresponding to a displacement distance of an electrode of a pixel beyond an instability point of the electrode; and
outputting a periodic voltage to a base electrode in response to the periodic signal, the periodic voltage causing spring legs of the electrode to vary displacement of the electrode with respect to the base electrode according to the periodic voltage, the displacement including distances beyond the instability point.

14. The computer readable storage medium of claim 13 , wherein the method includes transmitting at least one of periodic voltage data or sampling data to a receiving device.

15. The computer readable storage medium of claim 13 , wherein outputting the periodic voltage allows the spring legs to displace the electrode beyond the instability point without collapsing.

16. The computer readable storage medium of claim 13 , wherein the periodic voltage is at least one of a digital pulsing signal or a sinusoid.

17. The computer readable storage medium of claim 13 , wherein the method includes:
when the displacement distance is less than the instability point of the electrode: determining a stable signal corresponding to the displacement distance; and, in response to the stable signal, outputting a stable voltage to the base electrode to cause the spring legs to displace the electrode to the displacement distance.

18. The computer readable storage medium of claim 13 , wherein the electrode is coupled to a mirror.

Assignees

• Texas Instruments Inc

Inventors

• Fruehling Adam Joseph
• Hall James Norman

Classifications

• B81B2201/042

  Micromirrors, not used as optical switches · CPC title

• B81B3/0037

  For increasing stroke, i.e. achieve large displacement of actuated parts · CPC title

• G02B26/0841

  the reflecting element being moved or deformed by electrostatic means · CPC title

• G02B26/06 Primary

  for controlling the phase of light (G02B26/08 takes precedence {, measuring optical phase difference G01J9/00}) · CPC title

• B81B2201/04

  Optical MEMS · CPC title