METHOD AND DEVICE FOR WRITING AND/OR READING OPTICAL INFORMATION Russian patent published in 2002 - IPC

FIELD: optical instrumentation engineering; writing and reading optical information. SUBSTANCE: method includes organization of reference and operating optical channels on one side of data medium 3; disposition of optically addressed spatial light modulator (OASKLM) 7 in reference-channel output pupil plane joined with operating-channel input pupil plane. Reference-channel light beam is divided into two relatively coherent components of which one is directed to OASLM 7 and other component is first conveyed to data medium 3 and then (upon its reflection from surface of medium 3), to OASLM and mixed up with first one. Definite correlation is set between total longitudinal increase in reference and operating channels and wavelengths of reference and operating radiations. Operating radiation is conveyed to OASLM in opposition to reference one and wave diffracting in first order is focused on data medium. Device implementing this method has two radiation sources 1 and 2, light splitter 4, set of mirrors 8, optical addressed spatial light modulator (OASLM) 7, information lens 6, and image detector. Device uses inertialess self-focusing system for data writing and reading. EFFECT: enhanced quality; reduced requirement to quality of optical elements. 6 cl, 1 dwg