Patent Number: 6,298,028

Title: Optical head and information recording and reproducing apparatus using it

Abstract: In an optical head for recording on or reproducing from a plurality of kinds of optical information recording media corresponding to a plurality of kinds of different wavelengths, coma aberration is prevented, and low price and high reliability are realized. To that end, in an optical head constituted by laser light sources of three wavelengths and photodetectors corresponding to the laser light sources of the three wavelengths, a two-laser module including laser light sources of two adjacent wavelengths and photodetectors corresponding to the laser light sources, a laser module including a laser light source of the rest one wavelength and a photodetector corresponding to the laser light source, and a dichroic mirror bonded with a rising mirror are combined.

Inventors: Arikawa; Kouji (Hitachinaka, JP), Nakamura; Shigeru (Tachikawa, JP), Shigematsu; Kazuo (Yoshikawa, JP)

Assignee: Hitachi, Ltd.

International Classification: G11B 19/12 (20060101); G11B 7/125 (20060101); G11B 7/135 (20060101); G11B 7/13 (20060101); G11B 7/12 (20060101); G11B 7/09 (20060101); G11B 007/12 ()

Expiration Date: 10/02/2018