Arrangement for aligning the image of an information structure on a converter

Claim 1

An arrangement for focussing an image of an information structure which is disposed on or in a substantially flat record carrier on a transducer by means of an optical element, comprising a light-sensitive detector, a light source aligned with the optical element for projecting light on the record carrier, means comprising said optical element for projecting light from the record carrier onto said light-sensitive detector, a control system which controls the optical element connected to said light-sensitive detector for controlling the focussing motion of said optical element, and a velocity detector connected to a non-linear velocity correcting means for supplying an electrical signal which is a measure of the velocity of movement of the optical element, said velocity correcting means being operative for detected velocities in excess of a predetermined velocity range, the output of the velocity correcting means being connected to a second input of a control system as a velocity feedback signal whereby detected velocities in excess of said predetermined velocity range are corrected.