Accession Number:

ADA455649

Title:

Fast Multi-Spectral Liquid-Crystal-On Silicon Spatial Light Modulators (Preprint)

Descriptive Note:

Conference paper

Corporate Author:

DISPLAYTECH INC LONGMONT CO

Personal Author(s):

• McNeil, John R.
• O'Callaghan, Michael J.
• Handschy, Mark A.
• Zhang, Guoqiang
• Glushchenko, Anatoliy
• West, John L.
• Lane, Kerry
• Gaalema, Stephen D.

Report Date:

2006-09-01

Pagination or Media Count:

10.0

Abstract:

The stressed liquid-crystal SLC electro-optic effect promises fast electro-optic response times even for design wave-lengths in the infrared IR. Here we report characteristics of SLC devices appropriate for use as liquid-crystal-on-silicon LCOS spatial light modulators SLMs in the near-IR band lambda 1.8 to 2.5 mum, mid-IR band 3 to 5.5 mum and far-IR band 8 to 14 mum. For these three bands, we fabricated SLC devices with 5, 10, and 20 mum thicknesses at drive voltages of 25, 50, and 125 V, respectively, these devices gave half-wave modulation with response speeds in the 1.3 to 1.6 ms range. Visible-light measurements on a 20-mum-thick SLC device between crossed polarizers gave a contrast ratio of 3601 which improved to nearly 18,0001 with a Babinet-Soleil compensator offsetting residual SLC retardance. The drive voltages for near-IR and mid-IR devices enable fabrication of SLCOS devices using high-voltage transistors options in standard CMOS processes improvement of SLC materials by modest increase of birefringence delta n and dielectric anisotropy delta e would further bring far-IR devices within the standard CMOS drive voltage range. High-voltage CMOS transistor design rules permit pixel pitches less than 24 mum, making 1000 x 1000 SLMs feasible.

Descriptors:

• *LIQUID CRYSTALS
• *LIGHT MODULATORS
• ELECTROOPTICS
• SILICON
• HIGH VOLTAGE
• CROSS POLARIZATION
• INTERMEDIATE INFRARED RADIATION
• BEAM STEERING
• REACTION TIME

Subject Categories:

• Physical Chemistry
• Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE