Intelligent self-healing of electrowetting devices

Patent metadata

Field	Value
Publication number	US-10175470-B2
Application number	US-201715421896-A
Country	US
Kind code	B2
Filing date	Feb 1, 2017
Priority date	Feb 1, 2017
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

The disclosed examples relate to methods and systems facilitate self-healing of regions of electrowetting devices. Electrowetting devices may be coupled to a switchable AC/DC electrical power supply that provides AC power to the electrowetting device to control electrowetting device operation and DC power to promote self-healing of the electrowetting device. A monitoring circuit outputs a signal in response to electrical power supply operating characteristic changes due to a failure of the electrowetting device's dielectric. The controller, responding to the signal, switches the power supply output from AC power to DC power to the electrowetting device. In response to the DC power, the electrowetting device responds by healing the degraded dielectric. When the failure is determined to be corrected, the power supply output is switched from DC power to AC power to the electrowetting device. The number of times self-healing is applied may be tracked for future analysis.

First claim

What is claimed is:

1. A control system, comprising:
a switchable alternating current/direct current (AC/DC) electrical power supply selectively switchable between providing AC electrical power and DC electrical power to an electrowetting device;
a monitoring circuit coupled to the switchable AC/DC electrical power supply, the monitoring circuit configured to output a signal relative to an operating characteristic of the AC/DC electrical power supply, wherein the operating characteristic changes based on an operating status of the electrowetting device; and
a controller coupled to the monitoring circuit and the switchable AC/DC electrical power supply that switches the AC/DC electrical power supply to outputting DC power in response to a signal from the monitoring circuit generated in reaction to a change in the operating characteristic of the AC/DC electrical power supply,
wherein the change in the operating characteristic of the AC/DC electrical power supply caused by a failure in a dielectric of the electrowetting device.

2. The system of claim 1 , wherein the switchable AC/DC electrical power supply comprises:
a variable input DC electrical source responsive to control signals from the controller, the variable input DC electrical source coupled to the monitoring circuit;
a waveform generator coupled to the variable input DC electrical source and the controller, the waveform generator outputting variable AC electrical power based on waveform control signals received from the controller and a DC input received from the DC electrical source;
a transformer coupled to the waveform generator that transforms an AC electrical signal generated by the waveform generator into a transformed AC electrical power;
a rectifier circuit coupled to receive the transformed AC electrical power from the transformer and configured to rectify the transformed AC electrical power; and
a controllable switch coupled to an output of the transformer and to an output of the rectifier, the controllable switch configured to selectively connect one of the output of the transformer and the output of the rectifier to electrodes of the electrowetting device in response to a signal from the controller.

3. The system of claim 1 , wherein the monitoring circuit comprises:
a voltage source coupled to output a voltage in response to an increase in current output by the switchable AC/DC electrical power supply,
wherein the increase in current output is the operating characteristic of the switchable AC/DC electrical power supply.

4. The system of claim 3 , wherein the monitoring circuit further comprises:
an amplifier for amplifying the voltage output by the voltage source.

5. The system of claim 1 , wherein the controller comprises:
an analog to digital converter, the analog to digital converter coupled to the monitoring circuit,
wherein an analog output from the monitoring circuit is converted to a digital output, wherein the digital output is indicative of an amount of failure of the dielectric of the electrowetting device.

6. The system of claim 1 , further comprising:
an electrowetting device fluidically sealed and having an interior space, the electrowetting device comprising:
a first fluid having a first index of refraction;
a second fluid having a second index of refraction different from the first index of refraction, wherein:
the first and second fluids are within the interior space of the electrowetting device,
the first and second fluids are immiscible, and
the first fluid is conductive; and

electrodes positioned about the electrowetting device coupled to the first fluid and to the switchable AC/DC electrical power source, wherein the first fluid is responsive to electrical power applied to the electrodes from the switchable AC/DC power supply.

7. The system of claim 1 , further comprising:
a variable DC offset power supply coupled to the controller and the switchable AC/DC electrical power supply, the variable DC offset power supply configured to supply a DC power offset to the AC power supplied by the AC/DC electrical power supply to the electrowetting device in response to a DC offset signal from the controller.

8. A self-healing electrowetting system, comprising:
an electrowetting device comprising:
a conductive first fluid having a first index of refraction within an interior of the electrowetting device;
a second fluid having a second index of refraction within the interior space of the electrowetting device, wherein the first fluid is conductive, and the first and second fluids are immiscible; and
a dielectric;
an anode associated with the dielectric; and
a cathode;

a switchable alternating current/direct current (AC/DC) power supply coupled to the anode and cathode of the electrowetting device, and configured to selectively switch between providing AC power and DC power to the electrowetting device in response to a control signal, the switchable AC/DC power supply having an operating characteristic indicating a normal operation of the electrowetting device;
a monitoring circuit coupled to the switchable AC/DC electrical power supply, the monitoring circuit configured to detect a change of the operating characteristic of the AC/DC electrical power supply, wherein the change in operating characteristic is in response to a failure of the dielectric of the electrowetting device ; and
a controller coupled to the monitoring circuit and the switchable AC/DC electrical power supply, the controller configured to:
in response to receiving a signal from the monitoring circuit indicating the change in the AC/DC electrical power supply operating characteristic, switch the AC/DC electrical power supply from outputting AC power to outputting DC power to the electrowetting device to repair the degraded dielectric;
determine the failure has been corrected; and
after determining the failure has been corrected, switch the AC/DC electrical power supply from outputting DC power to outputting AC power to the electrowetting device.

9. The self-healing electrowetting system of claim 8 , wherein the monitoring circuit is configured to detect a change in current output by the AC/DC electrical power supply in response to the failure of the dielectric of the electrowetting device.

10. The self-healing electrowetting system of claim 8 , wherein the monitoring circuit comprises:
a voltage source coupled to output a voltage in response to an increase in current output by the switchable AC/DC electrical power supply; and
an amplifier for amplifying the voltage output by the voltage source, wherein the increase in current output is the operating characteristic of the AC/DC electrical power supply.

11. The self-healing electrowetting system of claim 8 , further comprising:
a variable DC offset power supply coupled to the controller and the switchable AC/DC electrical power supply, the variable DC offset power supply configured to supply, in response to a DC offset signal from the controller, a DC power offset to the AC power supplied by the AC/DC electrical power supply to the electrowetting device.

12. The self-healing electrowetting system of claim 8 , wherein the controller further comprises an analog-to-digital converter coupled to the monitoring circuit.

13. The self-healing electrowetting system of claim 8 , wherein the controller is further configured to:
in response to receiving a signal from the monitoring circuit indicating the failure of the dielectric is repaired, switching the AC/DC electrical power supply to output AC power to the electrowetting device according to a beam steering and/or shaping signal.

14. The self-he

Assignees

• Abl Ip Holding Llc

Inventors

• Malone Gregory

Classifications

• G02B26/005 Primary

  based on electrowetting · CPC title

• H02M3/33507

  with automatic control of the output voltage or current, e.g. flyback converters (H02M3/33561, H02M3/33569 take precedence) · CPC title