OPTICAL INFORMATION RECORDING AND REPRODUCING DEVICE

• Main Author: USUI MASAYUKI
• Format: Patent
• Language: English
• Published: 12.09.1990
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

PURPOSE:To promote the reliability by providing a means for restricting an adjusting range by a direction adjusting means for adjusting light beam spots in the abreast direction of tracking tracks and setting a mutual distance between the light beam spots in one pair as not exceeding double the pitch of the tracking tracks. CONSTITUTION:A diffraction grating 13 is operated to turn in the direction of an arrow A-A' by a diffraction grating turning means. Hereupon, a holder 51 is freely turnably supported as to be turnable in a range of a turning angle of A-A' with a frame 50 constituting a head main body. The turning amt. of the holder 51 is limited to a moving range of a protrusion 51a in a notched part of the frame 50, and the middle A0 of the moving range is assumed as a target for adjustment. Then, the distance between the projections of two beam spots S1 and S2 in the abreast direction of the tracking tracks is restricted to not exceeding double the track pitch. By this method, the abreast direction of three beam spots can be set in a univocal and simple method as against the tracking tracks with a prescribed pitch in parallel, thus promoting the reliability and also contriving reduction of cost for manufacturing and adjustments.