Abstract

Parallel access to optical disks is a promising technique for increasing data transfer rate from mass storage and is a natural extension of optical imaging.^[1] The nature of the lens design for parallel access is however, considerably different than for serial access and is primarily limited by aberrations and vignetting rather than by diffraction. Furthermore, tolerancing issues related to disk and head manufacture as well as environmental effects are more critical in the parallel access case and hence must play a greater role in design tradeoffs. In this paper we will discuss a number of design issues related to maximizing the parallelism associated with access to optical disk while maintaining low head mass to facilitate the increased difficulty of adaptive alignment (i.e. tracking, focus, tilt). The ultimate goal of this study is to achieve maximum aggregate data rate. Primarily, we will treat sustained data rate but the low mass characteristic of our designs will tend to improve tracking and seek times as well.

© 1994 Optical Society of America