A spinstand motion platform is for electronic head and disk testing equipment. The platform has very dense diskdrive track pitches that precisely position three axes with air bearings. Both the xy stage and spindle are mounted to a granite base connected to the machine stand by vibrationisolation mounts. A heterodyne laser interferometer helps control position feedback of the read/write head over the disk with 0.6nm resolution and 25nm repeatability.
Silicon photodiode