摘要 |
An optical head includes a beam-generator, a slab type waveguide, an output hologram coupler, a focal lens, an input hologram coupler, and a photoelectric transducer. The slab type waveguide has a cladding, and a first core and a second core formed on opposite side surfaces of the cladding. The output hologram coupler is provided on the slab type waveguide for decoupling a beam emitted from the beam-generator and guided through the second core. The focal lens focuses a beam decoupled in the output coupler and transmitted through the cladding and the first core onto an optical recording medium. The input hologram coupler is provided on the slab type waveguide for coupling to the first core a beam reflected from the optical recording medium and led to the lens. The photoelectric transducer detects the beam coupled to the input coupler and guided through the first core. With this arrangement, it is possible to reduce thickness of the optical head, achieve highly accurate positioning on the slab type waveguide and the photoelectric transducer, and enhance the beam utilization efficiency.
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