| 摘要 |
PURPOSE:To reduce the size in an optical axis direction and to make constitution simple by forming a composite coil body in a prescribed state to a bobbin which supports an optical lens and conducting prescribed currents corresponding to error signals to the respective coils. CONSTITUTION:Luminous fluxes for the purpose of reproduction and readout out are collected into the information bits, etc. on a disc, and tracks are traced. An optical lens 10 is supported with the supporting part 11a of a bobbin 11. The bobbin 11 has the supporting part 11a of the lens at one end and a composite coil body 12 including three coils is wound around the cylindrical part 11b concentrical therewith. The body 12 is inserted into the gap 16 of a magnetic circuit consisting of a magnet 13 and yokes 14, 15. The respective currents of time axis error signals, track error signals and focus error signals calculated in accordance with the detection signals of sensors for detecting errors are conducted to the three coils. |
