Method of manufacturing spatial light modulator and electronic device employing it

• US 6,650,461 B2
• Filed: 07/10/2002
• Issued: 11/18/2003
• Est. Priority Date: 12/01/1995
• Status: Expired due to Fees

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Yotsuya, Shinichi, Koeda, Hiroshi, Atobe, Mitsuro
• Primary Examiner(s): Spector, David N.
• Application Number:
  US10/192,111
• Publication Number:
  US 20030016435A1
• Time in Patent Office: 496 Days
• Field of Search: 359/290, 359/291, 359/292, 359/295, 353/31, 353/37
• US Class Current: 359/291
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A spatial light modulator is constructed from a conductive silicon mirror substrate and a glass electrode substrate including sodium, anode-bonded together. The silicon mirror substrate has micromirrors arranged in a matrix, torsion bars coupling these micromirrors in the x-direction, and a frame coupled to both ends of the torsion bars. A glass electrode substrate has a central depression, a rim around the periphery thereof, pillars projecting from within the depression, and electrodes and wiring driving micromirrors formed within the depression in an inclining manner. Both ends of the torsion bars are bonded to the rim of the frame portion, and intermediate portions of the torsion bars are bonded to the pillars. Both ends of the torsion bars are cut away from the frame portion during dicing.

Claims

1. An optical card capable of optical switching comprising:

an insulating substrate;

a plurality of induction coils provided on the insulating substrate;

a spatial light modulator provided on the insulating substrate; and

a wiring pattern provided on the insulating substrate that connects the plurality of induction coils with the spatial light modulator; and

wherein the spatial light modulator comprises;

a plurality of micromirrors that reflect light;

a plurality of pillars that support the plurality of micromirrors; and

a plurality of electrodes that drive the plurality of micromirrors by a coulomb force; and

wherein each electrode is connected to a respective one of the plurality of induction coils.

2. The optical card of claim 1, wherein the plurality of induction coils generate induction voltages so as to drive the plurality of micromirrors when the plurality of induction coils are disposed opposite to corresponding reading-device induction coils arranged in a reading device.

3. The optical card of claim 1, wherein the plurality of electrodes are divided into pairs of electrodes, each pair of electrodes positioned opposite a respective one of the micromirrors and including a first electrode connected to one of the induction coils and a second electrode connected to another one of the induction coils.

4. The optical card of claim 1, wherein each of the micromirrors has a reflective layer on a front surface that reflects the light.

5. The optical card of claim 4, wherein each of the pillars supports the corresponding micromirrors at a back surface opposite to the front surface.