| 摘要 |
PROBLEM TO BE SOLVED: To attain to be small in size and low in cost by making a hologram and a light receiving means in common with each other, and at the same time to obtain a favorable signal by decreasing aberration and offset of signal due to positional deviation of two laser beam sources, in an optical pickup device having a plurality of light sources with different wave length. SOLUTION: In an optical pickup device which has a plurality of light sources 1, 2 comprising semiconductor laser with different wave length, projects a luminous fluxes from a plurality of light sources through an optical means 3 leading to an optical recording medium 7 on a recording surface on the optical recording mediun, and executes writing, erasing or reproducing of information while receiving return luminous fluxes reflected by the recording surface through a light receiving means 9, the optical means 3 leading the luminous fluxes from a plurality of light sources to the optical recording medium 7 is a nearly triangular prism which reflects the luminous fluxes from a plurality of optical sources 1, 2 by respective different reflection surfaces, and is composed of a hologram 4 having a function to make light beams of respective wave length converge on a same point of the light receiving means 9 between a plurality of light sources 1, 2 and the optical recording medium 7. |
