摘要 |
The optical head has a light source, a collimating lens, an aperture-limiting element and an objective lens in the mentioned order in the direction of progress of light emitted from the light source, and a photo-detecting system for detecting return light having been transmitted through the objective lens and reflected by an optical disk. The aperture-limiting element includes a plurality of stripe transparent electrodes spaced apart at a predetermined interval on an electro-optical crystal substrate, and a substantially circular non-electrode area lacking the stripe transparent electrodes at a center portion of the substrate. The aperture-limiting element can be constructed with a reduced number of components as compared with the prior art construction.
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