Research/Patents/US 5268862
US 5268862

THREE-DIMENSIONAL OPTICAL MEMORY

Assignee

REGENTS OF THE UNIVERSITY OF CALIFORNIA, THE, A CORP. OF CA

Filed

Apr 25, 1989

Granted

Dec 7, 1993

Location

IRVINE CA US

Abstract

An active medium, typically a photochromic material and more typically spirbenzopyran, maintained in a three-dimensional matrix, typically of polymer, is illuminated in selected regions by two UV laser light beams, typically of 532 nm. and 1064 nm. wavelength, to change from a first, spiropyran, to a second, merocyanine, stable molecular isomeric form by process of two-photon absorption. Regions not temporally and spatially coincidently illuminated are unchanged. Later illumination of the selected regions by two green-red laser light beams, typically of 1064 nm wavelength each, causes only the second, merocyanine, isomeric form to fluoresce. This fluorescence is detectable by photodetectors as stored binary data. The three-dimensional memory may be erased by heat, or by infrared radiation, typically 2.12 microns wavelength. Use of other medium permit the three-dimensional patterning of three-dimensional forms, such as polystyrene polymer solids patterned from liquid styrene monomer. Three-dimensional displays, or other inhomogeneity patterns, can also be created.

Source: Google Patents

35 USC §181 Secrecy Order

Imposed

Feb 26, 1991

Rescinded

Jul 29, 1992

Duration

1 year, 5 months

Inventor

  • 1PETER M. RENTZEPIS

Technology Domains

Click a domain to browse all patents in this category.

Back to patent indexSource: USPTO 35 USC §181 secrecy order records