| 摘要 |
An optical path splitting unit and an optical pickup employing the same are provided to make the polarization directions of beams emitted from and entering each light source/detection part perpendicular to each other in order to prevent the beams from returning to the light source/detection part. An optical path splitting unit(100) comprises a beam splitter(110), first polarization conversion mirrors(120) including first mirrors(130,140), and second polarization conversion mirrors(150) including second wave plates and second mirrors(160,170). The beam splitter polarizes beam of a first wavelength and reflects beam of a second wavelength. The first polarization conversion mirrors, placed at one side of the beam splitter, polarizes the first wavelength beam, and transmits the second wavelength beam. The second polarization conversion mirrors, placed at the other side of the beam splitter, polarizes the beam passing through the beam splitter. The beam splitter transmits the first polarization beam but reflects the second polarization beam perpendicular to the first polarization beam. |
