Rader, Fishman & Grauer PLLC
Optical pickup device and optical disk device and optical device and composite optical element
An optical pickup device is provided which includes a first diffraction grating (45) that splits a light beam emitted from a light-emitting/-detecting element (31) into a zero-order light beam and positive and negative first-order light beams, a second diffraction grating (46) that diffracts return light from an optical disk (2) for traveling along a light path separate from that of the outgoing light, and a third diffraction grating (47) that corrects the deviation of the light path by diffracting the positive first-order light beam diffracted by the second diffraction grating (46). The light-emitting/-detecting element (31) provides a focusing error signal FE by detecting the negative first-order light beam, and a tracking error signal by detecting return portions of the positive and negative first-order light beams from the first diffraction grating (45).
Sony Corporation
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inventional inventional inventional inventional additional additional additional
Tetsu Junichi Satoru Takeshi Masahiro Norio Kiyoshi
Tanaka Suzuki Ishii Kubo Saito Fukasawa Toyota