title: White light micrograting multiplexing for high density data storage.
abstract: Recording of multiplexed microholographic gratings with improved recording volume for high density optical data storage is proposed and demonstrated. By using a hybrid diffractive-refractive objective lens with extended depth of focus, we have achieved a recording beam size of approximately 1 microm and a focal depth of 20 microm. Multiple gratings corresponding to spectral lines within the 400-650 nm spectral band have been successfully multiplexed in a single recording spot or pit of size 1.25 microm on a DuPont photopolymer film using a white light source along with narrowband filters or dispersion elements, thus demonstrating the storage of multiple bits in a single pit. Simultaneous readout of multiple bits in a single storage pit is accomplished with a microspectrometer-type readout head using a white light source.
authors.affiliation: New Span Opto-Technology Incorporated, Miami, Florida 33173, USA.
authors.forename: Jame J
authors.initials: JJ
authors.lastname: Yang
authors.forename: Michael R
authors.initials: MR
authors.lastname: Wang