| 摘要 |
<p>PURPOSE: A focussing control device for an optical recorder is provided to precisely control the focussing of the optical recorder by controlling an interval between a focussing lens mounted to a body tube and a recording layer of a disc by an interval control element formed of a shape memory alloy. CONSTITUTION: A focussing control device for an optical recorder includes an interval control element(40) formed between a body tube(20) and a slider(30) with a shape memory alloy, and a control part for applying electric signals to the interval control element. The interval between the body tube and the slider is variable by the deformation of the shape memory alloy in response to the change of temperature.</p> |
