Industrial Technology Research Institute

Wei-Chih Lu

Der-Ray Huang

Jau-Jiu Ju

Mark O Freeman

Tzu-Ping Yang

Hsi-Fu Shih

Carl Y Yang

The present invention discloses a multiple-beam holographic optical pick-up head, which has the advantages of the multiple-beam optical pick-up head and the holographic optical pick-up head and can increase the light usage efficiency. This invention uses the property that a polarized diffractive optical element can generate different optical effects for laser beam with different polarizations and places a polarized multiple-beam grating and polarized hologram on the optical path for splitting the incident light toward the disc into multiple reading beams by the multiple-beam grating. The returning laser beams reflected from the disc are diffracted and diverted by the hologram to reach a photodetector. Both the incident and reflective beams are diffracted once only; thus the light usage efficiency can be increased.

Growing community of inventors

Tainan, Taiwan

Wei-Chih Lu