Disk reproduction apparatus capable of continuously varying a re

Disk storage device having light receiving device located at imp

Disk storage which automatically adjusts to optimum recording/re

Disk-based optical correlator and method

Distortion correction of a reconstructed holographic data image

Dividing marks in optical media to decrease adjacent track cross

Double refraction plate with refractive grating pattern around a

Drive current supply circuit with current mirror

Dual digital phase locked loop clock channel for optical recordi

Dual focus objective lens with two curvatures for focussing ligh

Dual optical pickup head for accessing both DVD and CD disc

Dual-focus optical pickup for different thicknesses of recording

Dual-wavelength optical recording head utilizing grating beam sp

Duel-layer optical scanner with non-periodic phase structure...

Dustproof case for an optical information tape including a clamp

DVD reading-writing pick-up head employing multiple wavelengths

DVD-RAM disc discriminative reproducing device

Dynamic record level control for optical disc recorder

Dynamic tracking control in an optical recording system by diffr