Optically Active Diffractive Device
KSU.141 - Optically Active Diffractive Device
The only real route to improving brightness of liquid crystal projection devices has been to improve light transmission of the liquid crystal devices. Liquid crystal devices typically have polarizers that immediately burn perhaps 50% of the light, and this has been a problem in providing high brightness LCD projection systems. Kent State inventors have developed a liquid crystalline diffractive light valve for use in diffractive projection systems. The liquid crystal cell includes substrates treated to provide alternating stripes which cooperate with the liquid crystal to form liquid crystal domains extending across the thickness of the cell that will produce a 180 phase difference in light emerging from adjacent domains, irrespective of the polarization of incident light.
• Electronic cinema, projectors, PC displays, television
• Phase gratings useful in light valve projectors
• Especially suitable for manufacture of large screen light valve projectors to produce bright, inexpensive large screen displays
Excellent optical efficiency independent of the polarization of incident light, eliminating the need for polarizers and the associated light loss. Easier to manufacture than currently proposed devices and does not require high resolution patterned electrodes. Cost savings.
Inventors: Philip J. Bos, David L. Johnson, Jianmin Chen, Hemasiri K. Vithana, William E. Glenn, Carvel E. Holton, Brett E. Smith
Patent Status: U.S. Patent 5,638,201
Associate Director, Technology Commercialization
Office: 330-672-3553 Fax: 330-672-7991