| 摘要 |
PURPOSE:To obtain an optical head which is small in size and light in weight by providing a slider which is made to float on a recording and reproducing surface through a gas layer, moving the position of the emission point of a laser light source with the aid of an emission point position varying means and focusing the convergent light of a light convergence means on the recording and reproducing surface. CONSTITUTION:Since the slider 16 floats by interposing an air layer between the recording and reproducing surface 4 and itself by the floating height decided by the circumferential speed of an optical disk 1, the shape of the slider 16 and the mass of a movable optical part 7, the floating height of the slider 16 on the outside circumference and the inside circumference of the optical disk 1 is different and a stop lens 15 causes defocusing on the recording and reproducing surface 4. Then, by making a current generated from a focus error signal which is detected by a photodetector 13 flow to the electrodes 20 and 21 of the lens part 18 of the laser light source 8, the beam waist position of emitted light 19 is moved in the direction of an optical axis. Besides, by diverging or converging the wave surface of the collimated light 6 of a collimating lens 11, the converging point of the stop lens 15 is focused on the recording and reproducing surface 4. Thus, an optical recording and reproducing device which does not have a moving part and which has the small and light optical head is obtained. |
