| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a small-sized and inexpensive optical head having three semiconductor lasers whose wavelengths are different from one another. <P>SOLUTION: The optical head has a 1st laser light source 2b which oscillates laser light at a 1st wavelength, a 2nd laser light source 2a which oscillates laser light at a 2nd wavelength, and a 3rd laser light source 1 which oscillates laser light at a 3rd wavelength. The optical head records, erases or reproduces information by irradiating an optical recording medium 12 with luminous fluxes which are selectively emitted from these 1st to 3rd semiconductor laser light sources 2a, 2b, 1 and pass through a common objective lens 6. An optical path composing means 4 which has a refracting surface 4a for combining at least two luminous fluxes among the luminous fluxes emitted from the 1st to 3rd laser light sources 2a, 2b, 1 into a roughly identical optical axis is arranged in an optical path between the 1st to 3rd laser light sources 2a, 2b, 1 and the objective lens 6. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
