Liquid crystal driver and optical head for tilt correction
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsKatsuhiko Yasuda, Hidenori Wada, Daisuke Ogata, Kanji Wakabayashi, Naoya Hotta
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AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsKatsuhiko Yasuda, Hidenori Wada, Daisuke Ogata, Kanji Wakabayashi, Naoya Hotta
Estimating the term…
Tilt which is inclination of a normal of optical disk relative to optical axis of optical head is corrected with a liquid crystal element. In a driver for the liquid crystal element, a periodic waveform generator generates periodic waveform and an inverting element inverts the periodic waveform. The periodic waveform and the inverted waveform are connected to two ends of a potential divider which provides partial voltages. The periodic waveform is connected to a common electrode of the liquid crystal element, and the partial voltages of the potential divider are connected to electrodes opposing the common electrode. A structure of a driver circuit for each direction is simple. Tilt in a plurality of directions can be performed independently of each other. Spherical aberration is also corrected. When the liquid crystal element is mounted to a fixed component, deterioration due to jitters is reduced.
An optical head comprising:
Dependencies are inferred from the claim text.