Patent ID: 6141301
Filing Date: 2000-10-31
Classification: G11B

Abstract:
In an optical storage system, an apparatus for focussing a light beam onto a recording medium, said apparatus comprising:a modulator for modulating said light beam to produce a modulated light beam;an objective lens for focussing said modulated light beam onto said recording medium;a focus detector for generating an electrical signal corresponding to a degree of focus of said modulated light beam in reference to said recording medium;a beamsplitter for directing said modulated light beam to said objective lens and directing a reflected light beam from said recording medium to said focus detector;a focus actuator placed in close proximity to said modulator, said actuator having a mirrored surface for reflecting said modulated light beam to said beamsplitter, wherein said focus actuator is moved in an optical axis responsive to said electrical signal generated by said focus detector.