Optical pick-up device
AssigneesKabushiki Kaisha Sankyo Seiki Seisakusho, Kabushiki Kaisha Toshiba
InventorsKatsushige Yanagisawa, Tohru Hotta, Ikuo Kasuga, Satoru Kishita
Life of this patent
Estimating the term…
Loading patent…
AssigneesKabushiki Kaisha Sankyo Seiki Seisakusho, Kabushiki Kaisha Toshiba
InventorsKatsushige Yanagisawa, Tohru Hotta, Ikuo Kasuga, Satoru Kishita
Estimating the term…
An optical system of an optical pick-up device 1 comprises a half mirror 13 and a prism 14 which serve to guide a first laser beam L1 for a CD and a second laser beam L2 for a DVD to the optical recording medium side and a common light receiving element 19. The half mirror 13 is set to have a ratio of a reflectance to a transmittance of 5:1 in the first laser beam L1 to be a P polarized light and the prism 14 is set to have a ratio of a reflectance to a transmittance of 1:3 in the first laser beam L2 having a P polarization component and an S polarization component mixed. The first laser beam for a CD can be guided to the optical recording medium without a light quantity loss. At the same time, a return light Lr can be sent in a sufficient light quantity back to the light receiving element 19 for servo signal generation. Therefore, it is possible to implement a reliable CD recording operation by using the first laser beam.
An optical pick-up device comprising:
An optical pick-up device comprising:
Dependencies are inferred from the claim text.