Optotech Inc, Colorado Springs, is anxious to have a format standard for 5.25 optical disks agreed quickly, and has proposed specifications to ANSI, the American National Standards Institute. Optotech claims that its proposal is the only one that fully specifies how to encode and decode data on disk, as well as the only one to couple track format with an error-correction code. The standards proposed by Optotech include a 512-byte sector size, continuous/composite grooves for tracking, and a two-of-seven encoding scheme with resynchronisation fields. The proposal also provides for a data banding technique in which the disk is banded into regions of identical angular velocities so that disk capacity approaches that of constant linear density without the seek-time penalties usually associated with constant linear velocity. In place of Optotech’s proposed single groove, another proposal put to ANSI recommends a sampled-servo format in which the disk would be pitted in a specific pattern to guide the head.
