Optical Track Position Indicators
Original Publication Date: 1988-Jan-01
Included in the Prior Art Database: 2005-Feb-14
In an optical disk, a recording layer has translucent chevron-shaped track position indicators. A laser beam impinging upon the recording layer is modulated in intensity by the translucent position indicators. Suitable detectors are provided for detecting the position indicator modulation and separating that modulation from the data indicating modulation caused by reflection of the laser beam by the recording layer. In a preferred form, a magneto-optic recording layer is employed for inducing light polarization rotational modulations rather than intensity modulations provided by the translucent position indicators. The geometric relationship between the chevron-translucent position indicators and the track alignment is shown.