Electrical characterization of interferometric modulators

• US 8,094,366 B2
• Filed: 08/26/2010
• Issued: 01/10/2012
• Est. Priority Date: 09/27/2004
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Cummings, William, Gally, Brian, Kothari, Manish
• Primary Examiner(s): Sugarman, Scott J
• Assistant Examiner(s): Thomas, Brandi
• Application Number:
  US12/869,494
• Publication Number:
  US 20100321761A1
• Time in Patent Office: 502 Days
• Field of Search: 359290-292, 359/295, 359/298
• US Class Current: 359/298
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/3466 based on interferometric effect

Abstract

Disclosed herein are methods and systems for testing the electrical characteristics of reflective displays, including interferometric modulator displays. In one embodiment, a controlled voltage is applied to conductive leads in the display and the resulting current is measured. The voltage may be controlled so as to ensure that interferometric modulators do not actuate during the resistance measurements. Also disclosed are methods for conditioning interferometric modulator display by applying a voltage waveform that causes actuation of interferometric modulators in the display.

Claims

1. A method of conditioning a microelectromechanical device, the method comprising:

applying a conditioning signal to a microelectromechanical device having an offset voltage of a first value, the conditioning signal having an average of a second value, wherein the second value is based, at least in part, on the first value.

2. The method of claim 1, wherein the second value is the same as the first value.

3. The method of claim 1, wherein the second value is non-zero.

4. The method of claim 1, wherein the conditioning signal is applied prior to the use of the microelectromechanical device.

5. The method of claim 1, wherein the voltage waveform includes an alternating square waveform.

6. A method of conditioning a microelectromechanical device, the method comprising:

determining an offset value based upon a first conditioning signal to at least one microelectromechanical device; and

applying a second conditioning signal to a second microelectromechanical device, the average value of the second conditioning signal being based, at least in part, by the determined offset value.

7. The method of claim 6, wherein the average value of the second conditioning signal is the same as the offset value.

8. The method of claim 6, wherein the average value of the second conditioning signal is non-zero.

9. The method of claim 6, wherein the conditioning signal is applied prior to the use of the microelectromechanical device.

10. The method of claim 6, wherein the voltage waveform includes an alternating square waveform.

11. A method of conditioning a microelectromechanical device, the method comprising:

applying a conditioning signal having a non-zero average to a microelectromechanical device such that the resultant offset voltage is less than would result from the same waveform with a zero average.