Multi-state shutter assemblies having segmented drive electrode sets

Patent metadata

Field	Value
Publication number	US-9217857-B2
Application number	US-201313796952-A
Country	US
Kind code	B2
Filing date	Mar 12, 2013
Priority date	Mar 12, 2013
Publication date	Dec 22, 2015
Grant date	Dec 22, 2015

Abstract

This disclosure provides systems, methods and apparatus incorporating display elements having light modulators that can operate in more than two states. In some implementations, the light modulator assembly includes an electrostatic actuator that includes a load electrode coupled to a shutter and a drive electrode set positioned proximate to the load electrode. The drive electrode set includes a plurality of discrete portions that are configured to drive the light modulator assembly to a plurality of different light modulator states. In some such implementations, the portions of the drive electrode set are positioned opposite to corresponding regions of the load electrode. In some implementations, the portions are arranged such that the portions are configured to electrostatically engage with adjacent regions of the load electrode.

First claim

What is claimed is:

1. An apparatus, comprising:
a light modulator;
a first electrostatic actuator configured to move the light modulator in a first direction, comprising:
a load electrode coupled to the light modulator; and
a drive electrode set positioned proximate to the load electrode, the drive electrode set including a plurality of discrete portions with a first portion opposing a first region of the load electrode and a second portion positioned opposing a second region of the load electrode, each portion electrically coupled to a separately controlled switch for controlling the application of an actuation voltage, wherein the first electrostatic actuator is configured to move the light modulator to a plurality of distinct light modulator states that are defined by a degree of actuation of the first electrostatic actuator, the plurality of distinct light modulator states including an open state, a closed state, and at least one intermediate state, each of the plurality of distinct light modulator states corresponding to a different number of portions to which the actuation voltage is applied; and

a second electrostatic actuator configured to move the light modulator in a second direction opposite the first direction.

2. The apparatus of claim 1 , wherein the load electrode is compliant and configured to deform towards the drive electrode set.

3. The apparatus of claim 1 , wherein the first region of the load electrode is electrically coupled to a second region of the load electrode via a serpentine member.

4. The apparatus of claim 1 , wherein a portion of the light modulator forms the second region of the load electrode.

5. The apparatus of claim 4 , wherein the first region of the load electrode is positioned between a first portion of the first drive electrode set and a first portion of the second drive electrode set; and
wherein the second region of the load electrode is positioned between a second portion of the first drive electrode set and a second portion of the second drive electrode set.

6. The apparatus of claim 5 , wherein the portions are arranged in a step-wise manner.

7. The apparatus of claim 1 , wherein each of the discrete portions of the drive electrode set has an actuation surface configured to electrostatically engage with a corresponding region of the load electrode.

8. The apparatus of claim 7 , wherein the portions are positioned such that the load electrode is positioned between the first portion and the second portion.

9. The apparatus of claim 1 , wherein the portions are arranged such that a distance separating the first portion and the load electrode is smaller than a distance separating the second portion and the load electrode.

10. The apparatus of claim 1 , wherein the first electrostatic actuator is configured such that:
when the first discrete portion is not electrostatically engaged with the first region, a first end point of the first discrete portion is separated from the first region of the load electrode by a first distance,
when the first discrete portion is electrostatically engaged with the first region of the load electrode, a second end point of the second discrete portion is separated from the second region of the load electrode by a second distance, and
the first distance is smaller than the second distance.

11. The apparatus of claim 1 , further comprising:
a substrate having an aperture formed therein;
wherein the light modulator is supported over the aperture; and
wherein the light modulator is configured to move to a partially light transmissive state when the first discrete portion is electrostatically engaged with the first region of the load electrode and configured to move to a completely light transmissive state when the second discrete portion is electrostatically engaged with the second region of the load electrode.

12. The apparatus of claim 1 , wherein the light modulator, the first electrostatic actuator, and the second electrostatic actuator form a display element, the apparatus further including:
a display including an array of display elements;
a processor that is configured to communicate with the display, the processor being configured to process image data; and
a memory device that is configured to communicate with the processor.

13. The apparatus of claim 12 , further comprising:
a driver circuit configured to send at least one signal to the display; and wherein
the controller further configured to send at least a region of the image data to the driver circuit.

14. The apparatus of claim 12 , further comprising:
an image source module configured to send the image data to the processor, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

15. The apparatus of claim 12 , further comprising:
an input device configured to receive input data and to communicate the input data to the processor.

16. An apparatus, comprising:
a light modulator;
a first electrostatic actuator configured to move the light modulator in a first direction, comprising:
a compliant load electrode coupled to the light modulator; and
a drive electrode set positioned opposing the load electrode, the drive electrode set including a plurality of electrically coupled discrete portions, each portion comprising a drive beam coupled at one end to a different drive beam anchor, with a first portion opposing a first region of the load electrode and a second portion positioned opposing a second region of the load electrode, the portions arranged in a step-wise manner such that a distance between the first portion and the first region of the load electrode is smaller than a distance between a the second portion and the second region of the load electrode when the first electrostatic actuator is in a relaxed state, wherein the first electrostatic actuator is configured to drive the light modulator to a plurality of distinct light modulator states, the plurality of distinct light modulator states including an open state, a closed state, and at least one intermediate state and each of the plurality of distinct light modulator states corresponding to a magnitude of an actuation voltage applied; and

a second electrostatic actuator configured to move the light modulator in a second direction opposite the first direction.

17. The apparatus of claim 16 , wherein the first portion is configured to electrostatically engage the first region of the load electrode and the second portion is configured to electrostatically engage the second region of the load electrode.

18. The apparatus of claim 16 , wherein a first region of the load electrode is electrically coupled to a second region of the load electrode via a serpentine member.

19. The apparatus of claim 16 , wherein a portion of the light modulator comprises the second region of the load electrode.

20. The apparatus of claim 19 , wherein the first region of the load electrode is positioned between a first portion of the first drive electrode set and a first portion of the second drive electrode set; and
wherein the second region of the load electrode is positioned between a second portion of the first drive electrode set and a second portion of the second drive electrode set.

21. The apparatus of claim 16 , wherein the first electrostatic actuator is configured such that:
when the first discrete portion is not electrostatically engaged with the first region, a first end point of the first discrete portion is separated from the first region of the

Assignees

• Pixtronix Inc

Inventors

• Wang Ye
• Brosnihan Timothy J

Classifications

• G02B26/02

  for controlling the intensity of light {(G02B26/004 takes precedence)} · CPC title

• G02B26/023 Primary

  comprising movable attenuating elements, e.g. neutral density filters · CPC title

• G02B26/00 Primary

  Optical devices or arrangements for the control of light using movable or deformable optical elements (control of light by modification of the optical properties of the media of the elements involved therein G02F1/00) · CPC title

• G02F1/292

  by controlled diffraction or phased-array beam steering (controlled diffraction for optical switching G02F1/31) · CPC title

• G02F2203/24

  beam steering · CPC title