optical head device

Abstract

Abstract PURPOSE:To simplify the construction and to make a titled device lightweight by the constitution that luminous flux from each light source is led to a focusing means via an optical wave guiding means such as plural optical fibers and using plural optical spots to record and reproduce information thereby reducing remarkably the number of optical elements. CONSTITUTION:The optical fibers 61, 62 have a definite outer diameter in the range of diameter of 125mum-60mum normally and a stable optical spot interval is set by arranging the optical fibers adjacently. Further, the core diameter of the optical fibers is nearly 8mum and divergent light having a beam waste of nearly N.A.0.1 set as the irradiated end face is irradiated. Thus, a collimation lens 53 having a focus of 20mm. and an effective diameter of nearly 4mm. is used, then the 1st wavelength light 63 and the 2nd wavelength light 64 are made easily to parallel light. The two luminous fluxes are reflected by a beam splitter 22, condensed on an information recording face 25 of a disc 24 via a condenser lens 23 to form two optical spots.

Inventors

• 👤 Tetsuo Kuwayama
• 👤 桑山　哲郎
• 👤 Kazuya Matsumoto
• 👤 和也 松本

Bibliographic Details