| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical head device capable of obtaining a stable reproducing signal when information is reproduced from a recording medium of a specification corresponding to a wavelength by selectively using laser beams having the wavelengths different from one another and to provide an information recording and reproducing device. <P>SOLUTION: The optical disk device 1 has first to third light sources 21, 22 and 23, wavelength selection films (optical coupling prisms) 32 and 33 correlated to arrangement of respective light sources and a polarization beam splitter 37. In the polarization beam splitter 37, an output for a power monitor can be separated. By adopting the arrangement of such optical elements, not only an objective lens 31 is made one three-wavelength compatible type but also the stable reproducing signal can be obtained when information is reproduced from the optical medium of a specification corresponding to the wavelength by selectively using the laser beam having wavelengths different from one another. <P>COPYRIGHT: (C)2007,JPO&INPIT |
