摘要 |
This invention relates to an optical pickup system which can detect focus errors and tracking errors without using diffraction grating. The optical pickup system comprises a laser diode for emitting laser beams, an objective lens for focusing the laser beam from the laser diode onto an optical disc, a two division hologram positioned between the laser diode and the objective lens for diffracting beams after separating a reflected beam reflected at the optical disc and passed through the objective lens into a first laser beam and a second laser beam along an tangential line to a track of the optical disc, and a four division photodetector for focusing the two laser beams diffracted by the two division hologram.
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