System and method for addressing a MEMS display

• US 7,142,346 B2
• Filed: 02/04/2005
• Issued: 11/28/2006
• Est. Priority Date: 12/09/2003
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Chui, Clarence, Mignard, Marc, Mathew, Mithran C.
• Primary Examiner(s): Ben, Loha
• Assistant Examiner(s): CHOI, WILLIAM C
• Application Number:
  US11/051,251
• Publication Number:
  US 20050206991A1
• Time in Patent Office: 662 Days
• Field of Search: 359/238, 359/245, 359/276, 359/277, 359290-292, 359/298, 359/315, 359/316
• US Class Current: 359/290
• 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 2300/06 Passive matrix structure, i.e. with direct application of both column and row voltages to the light emitting or modulating elements, other than LCD or OLED
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/207 by domain size control G09G3/3637 takes precedence
• CPC Class Codes: G09G 3/2074 using sub-pixels
• CPC Class Codes: G09G 3/3466 based on interferometric effect

Abstract

A system and method for addressing an array of MEMS display elements, such as interferometric modulators, from a drive control. A display includes groups of display elements that are addressed with a commonly applied drive signal. In one embodiment, the groups of display elements are configured to have different response times and are driven by pulses of varying length indicative of those response times. In another embodiment, the groups of display elements are configured to have different actuation voltages and are driven by pulses of varying voltage indicative of those actuation voltages.

Claims

1. A light modulator comprising:

an array of elements at least some of which have different values of deflection versus addressing pulse width; and

addressing circuitry configured to provide addressing pulses of varying width to the array of elements such that different combinations of elements switch in a selectable manner, depending upon the width of the addressing pulses.

2. The light modulator of claim 1, wherein at least some different elements of said array have differing mechanical structures to effect differing values of deflection versus addressing pulse width.

3. The light modulator of claim 2, wherein different elements of said array have differing spring constants for deflectable portions of the elements.

4. The light modulator of claim 1, wherein at least some different elements of said array have differing resistor-capacitor (RC) time constants to effect differing values of deflection versus addressing pulse width.

5. The light modulator of claim 1, wherein different elements of said array have differing film thicknesses to effect differing values of deflection versus addressing pulse width.

6. The light modulator of claim 1, further comprising at least one of a resistor or capacitor in series with at least one addressing line.

7. A light modulator comprising:

an array of elements having differing values of deflection versus applied voltage; and

addressing circuitry configured to provide addressing pulses of varying voltage level to the array of elements such that different combinations of elements switch in a selectable manner, depending upon the voltage level of the addressing pulses.

8. The light modulator of claim 7, wherein at least some different elements of said array have differing mechanical structures to effect differing values of deflection versus applied voltage.

9. The light modulator of claim 7, wherein at least some different elements of said array have differing film thicknesses to effect differing values of deflection versus applied voltage.

10. The light modulator of claim 9, wherein the differing film thicknesses comprise differing thicknesses of an insulator layer between a deflecting and non-deflecting electrode.