Optics For Multibeam Optical Disk Systems (OMODS)

Abstract
Optical disc recorder systems are being developed for ultra-high data rate, high-density applications. These systems utilize multiple independently modulated laser beams to simultaneously record closely spaced tracks of data with near diffraction limited performance. The record and playback laser source for these systems is an argon laser whose output is efficiently split into the number of beams needed to achieve the desired data rates. Two techniques for beamsplitting were evaluated -- acousto-optic deflectors and phase gratings. The record beams are passed through a multiple transducer A-0 modulator to encode the desired information to be recorded and focused onto the optical disc to form closely spaced tracks. A second set of low-power unmodulated beams pass through the same optical system and are focused onto the optical disc to allow playback while recording for data verification purposes. These same beams are also used for normal playback during subsequent data retrieval operations. The optical designs for these systems will be described and test results presented.