Scanner for signals on rotary disc concentric tracks - has scanning head guide along logarithmic spiral, starting in rotation centre.

摘要

The scanner picks up information signals from concentric tracks on a rotary disc. A scanning head (9) is guided along a logarithmic spiral (4), starting in the centre of rotation. The scanning head is fitted on a support such that the longitudinal axis of the support and scanning head enclose a fixed angle. The angle corresponds to the angle cut by the logarithmic spiral w.r.t. the tracks. The support is pref. strip-shaped, rolling with its end away from the scanning head on a member (12) shaped to match the evolvent of the logarithmic spiral. USE/ADVANTAGE - For computer hard (Winchester) disc drive or disc player. Simple design for scanning any disc dia. Excellent information reproduction with higher information track packing density possible.