Title:
【発明の名称】光ヘッド
Document Type and Number:
Japanese Patent JP2904422
Kind Code:
B2
Abstract:
An optical head wherein a required astigmatism can be obtained readily to facilitate production thereof and the linear distance between a face of an information record medium and a light receiving element is reduced to reduce the overall size and weight of the optical head. The optical head comprises a prism having a parallelogram shape in side elevation. The prism has a reflecting/transmitting face extending at an angle of about 45 degrees with respect to an optical axis to the information record face for reflecting light from a light source toward the information record face, first and second reflecting faces extending perpendicularly to the optical axis for successively reflecting light transmitted thereto through the transmitting face, and a transmission face extending in parallel to the reflecting/transmitting face. Light emerging from the transmitting face of the prism is received and converted into an electrical signal by a light receiving element.
Inventors:
SATO KATSUHARU
YANAGAWA NAOHARU
YANAGAWA NAOHARU
Application Number:
JP18451889A
Publication Date:
June 14, 1999
Filing Date:
July 19, 1989
Export Citation:
Assignee:
PAIONIA KK
International Classes:
G11B7/135; G11B7/1359; (IPC1-7): G11B7/135
Domestic Patent References:
| JP63136334A | ||||
| JP6352341A | ||||
| JP59128510A | ||||
| JP59142759A |