30 to 50 ns Liquid-Crystal Optical Switches
Abstract
The optical switching time of twisted-nematic liquid-crystal cells using the liquid crystals, 5CB, 50CB, and PCH5 have been characterized as a function of temperature, prebias voltage and switching voltage, V. The transition time from 90 % to 10 % transmission scales as V-1.9 and is limited to 30 to 50 ns by the liquid-crystal breakdown electric field. The time from the initial switching voltage step to 90 % transmission, delay time, decreases with increasing prebias and switching voltage. For 5CB and 50CS the delay time approaches a constant value at higher electric fields. Both the transition and delay times decrease with increasing temperature. The minimum transition time at temperatures a few degrees below the nematic-isotropic temperature are 32, 32, and 44 ns and delay times are 44, 25 and 8 ns for 5CB, 50CB and PCH5 respectively.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2010
- Accession Number
- ADA524121
Entities
People
- B. R. Kimball
- G. W. Turner
- M. W. Geis
- R. J. Molnar
- Richard M. Osgood
- T. M. Lyszczarz
Organizations
- Massachusetts Institute of Technology