| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical head device which causes no noise in a tracking error signal or the like even if recording and reproduction to multiple kinds of optical recording media are carried out with a plurality of laser beams different in wavelength by using a diffraction type objective lens. <P>SOLUTION: In the optical head device, a light-receiving element 15 and an optical system are constituted so that the light-receiving parts 151, 152 and 153 of the light-receiving element 15 may be located at an inner area to an annular flare high density area 100 generated in a returning light of a laser beam in which only a center side refraction surface area of a diffraction type objective lens is used. Consequently, such a flare is not detected by the light-receiving element 15 even if the flare high density area 100 is generated. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
