Optical system of optical information recording/reproducing apparatus
AssigneeAsahi Kogaku Kogyo Kabushiki Kaisha
InventorsKoichi Maruyana, Makoto Iwaki
Life of this patent
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Abstract
An optical system of an optical information recording/reproducing apparatus including a light source for emitting a generally parallel luminous flux; an objective optical system for converging the luminous flux emitted from said light source portion a medium; a beam splitter for splitting the luminous flux reflected by said medium from a light path directed to the light source portion and guiding the same to a light receiving system; a chromatic aberration correcting element having almost no power disposed between said objective lens and said beam splitter and adapted to correct a chromatic aberration of said objective lens; and means for independently actuating said objective lens at least in an optical axis direction thereof.
Claims15
An optical system of an optical information recording/reproducing apparatus including:
- a light source for emitting divergent luminous flux;
- an objective lens for converging the luminous flux emitted from said light source onto a medium;
- a beam splitter for splitting the luminous flux reflected by said medium from a light path directed to the light source and guiding the luminous flux to a light receiving system;
- and
- a chromatic aberration correcting element having substantially no power, said chromatic aberration correcting element positioned between said objective lens and said beam splitter, said chromatic aberration correcting element comprising means for correcting a chromatic aberration of said objective lens;
- said chromatic aberration correcting element being formed of a positive lens and a negative lens cemented together, said negative and said positive lens having substantially the same refractive index and different Abbe's number.
An optical system of an optical information recording/reproducing apparatus including:
- an objective lens for converging a generally parallel luminous flux;
- and
- a chromatic aberration correcting element having substantially no power for correcting chromatic aberration of said objective lens;
- said chromatic aberration correcting element is formed of a positive lens and a negative lens cemented together, said negative lens and said positive lens having substantially the same refractive index and different Abbe's number.
Dependencies are inferred from the claim text.