High Speed Integrated Light Modulators.
Abstract
This report describes the invention and development of the Grating Light Valve (GLV). The GLV is a deformable grating structure fabricated by silicon surface micromachining. It is a reflection phase grating; optical modulation is achieved by electromechanically controlling the grating amplitude. The GLV is a promising technology for spatial light modulators, and projection and head mounted displays. Bistable switching of the grating at speeds as fast as 20 ns has been demonstrated. Single-pixel contrast ratios of 200:1 have been measured. The GLV is inherently capable of color selection and, with a proper optical system, produces the full NTSC color gamut. Arrays of 150-by-192 pixels have been fabricated and operated to demonstrate the GLV's potential as a color display. The device fabrication process for the GLV is simple and compatible with CMOS processing. However, the first generation GLV suffers from surface adhesion (stiction) since it contains optically flat, compliant structures separated by submicron air gaps. Our second generation devices combine beam stiffening, surface modification, and novel selfaligned processes to avoid stiction and operate with high reliability.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1996
- Accession Number
- ADA308804
Entities
People
- D. M. Bloom
- F. A. Sandejas
Organizations
- Stanford University