STORAGE MEDIUM TRACK PITCH DETECTOR

摘要

The appts. includes a light system for projecting a spot of light onto at least a portion of one track and a photodetector for providing an electrical signal representative of a property of the light from the spot emerging from the medium in a predetermined direction. A tracking arrangement maintains a constant lateral spacing of the spot of light from another track parallel to the first. A scanning arrangement provides relative motion between the light system and the medium in a direction parallel to the second track. The appts. is capable of providing the track pitch measurement over the entire information area in a short time.