Optical pickup
AssigneeMitsumi Electric Co., Ltd.
InventorsTadashi Adachi, Hirokazu Furuse, Masayoshi Sugawara
Life of this patent
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Abstract
An optical pickup comprising: a diffraction grating, a beam splitter and laser beam guiding optical components that change direction of laser beams, which are placed on a light path constituted by a semiconductor laser that emits dual wavelength laser beams and an information recording surface of an optical disk, wherein a wavelength plate is provided on a light path between said diffraction grating and said semiconductor laser so that a laser beam irradiated on the recording surface of said optical disk becomes an elliptically polarized (including circularly polarized) beam or a beam having a polarizing plane that produces an angle of 30-60 degrees relative to a radius direction.
Claims4
An optical pickup comprising:
- a diffraction grating;
- a beam splitter;
- and
- laser beam guiding optical components that change direction of and converge laser beams, which are placed on a light path defined by a semiconductor laser that emits dual wavelength laser beams and an information recording surface of an optical disk, wherein,
- a wavelength plate is further provided on a light path between said diffraction grating and said semiconductor laser so that a laser beam irradiated on the recording surface of said optical disk becomes an elliptically-polarized (including circularly-polarized) beam or a beam having a polarizing plane that produces an angle of 30-60 degrees relative to a radius direction.
Dependencies are inferred from the claim text.