Objective optical system and optical pickup apparatus
AssigneeKonica Minolta Opto, Inc.
InventorsKazutaka Noguchi, Yuichi Atarashi
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Abstract
An objective optical system according to the present invention is provided for use in an optical pickup apparatus for recording or reproducing information on an information recording surface of a first optical information recording medium using a first light flux emitted from a first light source, and the objective system includes: a first lens with a positive reflective power including plastic; and a second lens with a positive refractive power including plastic. Opposite optical surfaces of the first lens are convex surfaces, and a refractive power of the first lens and a power of a whole system of the objective optical system satisfy the predefined condition.
Claims22
An objective optical system for use in an optical pickup apparatus for recording or reproducing information on an information recording surface of a first optical information recording medium with a protective layer with a thickness t1 using a first light flux with a wavelength λ1 emitted from a first light source, the objective optical system comprising:
- a first lens with a positive refractive power comprising plastic;
- and
- a second lens with a positive refractive power comprising plastic and arranged closer position to the first optical information recording media than the first lens,
- wherein opposite optical surfaces of the first lens are convex surfaces, and
- the objective optical system satisfies
- 0.04<P1/P<0.24
- where P1 is a refractive power of the first lens, and P is a power of a whole system of the objective optical system.
Dependencies are inferred from the claim text.