Systems and methods of actuating MEMS display elements

• US 7,560,299 B2
• Filed: 02/25/2005
• Issued: 07/14/2009
• Est. Priority Date: 08/27/2004
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Cummings, William J.
• Primary Examiner(s): Kebede; Brook
• Application Number:
  US11/159,073
• Publication Number:
  US 20060057754A1
• Time in Patent Office: 1,600 Days
• Field of Search: 438/38, 438/48, 438 50- 53, 438/57, 345 84- 90, 345/100, 345/108
• US Class Current: 438/48
• 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 2310/0254 Control of polarity reversal in general, other than for liquid crystal displays
• CPC Class Codes: G09G 2320/0204 Compensation of DC component across the pixels in flat panels
• CPC Class Codes: G09G 2320/0257 Reduction of after-image effects
• CPC Class Codes: G09G 3/3466 based on interferometric effect

Abstract

Methods of writing display data to MEMS display elements are configured to minimize charge buildup and differential aging. The methods may include writing data with opposite polarities, and periodically releasing and/or actuating MEMS elements during the display updating process. Actuating MEMS elements with potential differences higher than those used during normal display data writing may also be utilized.

Claims

1. A method of actuating a MEMS display element, said MEMS display element comprising a portion of an array of MEMS display elements, said method comprising:

writing display data of a first frame to said MEMS display element with only a potential difference of a first polarity during a display write process;

after said writing display data of a first frame, releasing said MEMS display element; and

after said releasing, writing display data of a second frame to said MEMS display element with a potential difference having only a polarity opposite said first polarity during a second portion of said display write process,

wherein each frame written during said display write process comprises different display data.

2. The method of claim 1, wherein one or more other frames of display data are written to said array between said first frame and said second frame.

3. The method of claim 1, comprising actuating said MEMS display element with a potential difference of said first polarity when writing a third frame during said display write process.

4. The method of claim 1, comprising alternately applying potential differences of opposite polarity to display elements of said array during alternating portions of said display write process.

5. The method of claim 4, wherein said alternating portions of said display write process comprise writing alternating frames of display data to said array of MEMS display elements.

6. The method of claim 5, wherein said alternating portions of said display write process comprise writing alternating rows of display data to said array of MEMS display elements.