optical pickup apparatus

Patent 5764613 Issued on June 9, 1998. Estimated Expiration Date:

April 30, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Near field and solid immersion optical microscope
Patent #: 5004307
Issued on: 04/02/1991
Inventor: Kino, et al.

Lithography system employing a solid immersion lens
Patent #: 5121256
Issued on: 06/09/1992
Inventor: Corle, et al.

Optical recording system employing a solid immersion lens
Patent #: 5125750
Issued on: 06/30/1992
Inventor: Corle, et al.

Optical disk data storage system with radiation-transparent air-bearing slider
Patent #: 5497359
Issued on: 03/05/1996
Inventor: Mamin, et al.

Inclination of an objective lens in an optical information system Patent #: 5553052
Issued on: 09/03/1996
Inventor: Oono, et al.

Inventors

Assignee

Sony Corporation

Application

No. 640209 filed on 04/30/1996

US Classes:

369/112.24, Plural distinct lenses359/664, Spherical369/43, WITH SERVO POSITIONING OF TRANSDUCER ASSEMBLY OVER TRACK COMBINED WITH INFORMATION SIGNAL PROCESSING369/44.14, Optical head servo system structure369/44.23Structure for shaping beam or causing astigmatic condition

Examiners

Primary: Nelms, David C.
Assistant: Chu, Kim-Kwok

Attorney, Agent or Firm

Kananen; Ronald P.

International Class

G11B 007/09

Foreign Application Priority Data

1995-05-18 JP

Abstract

An optical pickup apparatus is constructed of an objective lens for condensing a light beam emitted from a light source toward an optical recording medium, and a convex lens arranged between the optical recording medium and the objective lens in which a surface thereof upon which the luminous flux projected from the objective lens is incident is a convex spherical surface with a radius of curvature which is a predetermined value, and another surface thereof which is located near and opposite to a surface portion of the optical recording medium which is a plane. With this arrangement, a tolerance with respect to decentering of the convex lens in connection with the optical axis of the objective lens is increased, so that an occurrence of aberration is reduced.