In the optical disc player, there is a necessity to correct the jitter caused by the disc eccentricity and rotation irregularity as well as focusing. For this correction, there are both the electrical correction method using a two‐axis optical head with memory and the mechanical correction method of a three‐axis optical head. If the goal is the simplification of the electrical circuit and the lowering of cost, the latter method is advantageous. However, in the tilting of the conventional field lens, the motion of the lens occurs in the direction of track and jitter and, for those in which the numerical aperture is 0.55 and larger, since good convergence characteristics are not obtained with respect to tilting of the lens, the three‐axis method is hardly realized. Therefore, the lens holder is held by parallel plate springs of rubber material. Thus, by contriving the electrical circuit driving the lens holder for the center of gravity of the lens holder to coincide with the center of the drive, the rotation of the axis could be controlled and an actuator realizing only translational motion effectively in the direction of the three axes (balanced drive method) was proposed and realized. an optical head based on this method was constructed and, with a high‐density (Hi‐Vision laser diode type) disc, a MUSE signal signal‐to‐noise (SN) ratio above 36 dB could be realized and an excellent image was confirmed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.