Multi-level deformable mirror device with torsion hinges placed in a layer different from the torsion beam layer

• US 5,600,383 A
• Filed: 06/07/1995
• Issued: 02/04/1997
• Est. Priority Date: 06/29/1990
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Hornbeck, Larry J.
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): Cohen, Cheryl
• Application Number:
  US08/474,203
• Time in Patent Office: 608 Days
• Field of Search: 359/223, 359/224, 359/290, 359/291, 359/846, 359/318, 359/295, 348/770, 348/771, 437/228, 156/652
• US Class Current: 348/771
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field
• CPC Class Codes: H04N 9/3102 using two-dimensional electronic spatial light modulators micromechanical modulators as such G02B26/0833; liquid crystal modulators as such G02F1/13
• CPC Class Codes: H04N 9/3141 Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A bistable deformable mirror device (DMD) pixel architecture is disclosed, wherein the torsion hinges are placed in a layer different from the torsion beam layer. This results in pixels which can be scaled to smaller dimensions while at the same time maintaining a large fractional active area, an important consideration for bright, high-density displays such as are used in high-definition television applications.

Claims

1. A spatial light modulation device said device comprising:

a base layer;

a beam layer;

a beam support post;

a hinge supported by said base layer and connected to said rotatable layer by said beam support post wherein said hinge allows said rotatable area to move within a defined motion with respect to said base layer, said hinge lying in a plane separate from the plane of said rotatable layer;

a hinge gap between said base layer and said hinge allowing for movement of said hinge; and

a beam gap between said hinge and said beam layer allowing for movement of said beam layer.

2. The device set forth in claim 1 wherein said base layer includes discrete areas for providing signals for controlling said rotation of said rotatable layer.

3. The device set forth in claim 2 wherein said discrete areas include address electrodes.

4. The device set forth in claim 3 wherein said discrete areas further include address circuitry.

5. The device set forth in claim 2 further including a substrate layer containing control circuitry;

and

interconnection structure for communicating signals from said control circuitry to said discrete areas.

6. The device set forth in claim 5 wherein said control circuitry is constructed using CMOS technology.

7. The device set forth in claim 1, wherein said hinge gap is an air gap.

8. The device set forth in claim 1, wherein said beam gap is an air gap.

18. The device set forth in claim 7, wherein said hinge gap is an air gap.

19. The device set forth in claim 7, wherein said beam gap is an air gap.

9. An array of pixels, each pixel individually rotatable into at least two states, said array comprising:

a base structure for supporting all of said pixels of said array, said array being maintained in a plane separate from the plane of said base;

each said pixel defining a surface area, each said pixel being connected to an end of a beam support post and an intermediate portion which is supported by said base structure and connected to each said pixel through an opposite end of said beam support post, said intermediate portion is separated from said base structure by a hinge gap and from each said pixel by a beam gap and positioned therebetween for connecting said base structure to each said pixel by allowing each said pixel to deform with respect to said base.

10. The device set forth in claim 9 further comprising a HDTV system and wherein said array is the visual display of a high density television receiver.

11. The device set forth in claim 9 wherein said base structure includes discrete areas for providing signals for controlling said rotation of said pixels.

12. The device set forth in claim 11 wherein said discrete areas include address electrodes.

13. The device set forth in claim 12 wherein said discrete areas further include address circuitry.

14. The device set forth in claim 12 further including a substrate layer containing control circuitry;

and

interconnection structure for communicating signals from said control circuitry to said discrete areas.

15. The device set forth in claim 14 wherein said control circuitry is constructed using CMOS technology.

16. The device set forth in claim 9 further comprising a display system wherein said array is a portion of a visual display of said system.

17. The device set forth in claim 9 further comprising a printer system wherein said array is a portion of an imaging system of said printer system.