Establissements Pierre Angenieux Sa

Ronald C Wainwright

Robert M Pettigrew

John D Bradbrook

Nicholas M Goy

John D Anderson

A camera zoom lens system comprising; means for generating and storing a first information signal representing a predetermined position of the first movable lens group, means for generating a second information signal whose value determines a relationship between the respective positions of said first and second movable lens groups, first computing means for deriving from the stored first information signal a third signal representing the position to which the second movable lens group must move so that both lens groups produce an in-focus image of the object at infinity, second computing means responsive to the first and second information signals for generating a correction signal which when combined with the third signal produces an output signal representing the position to which the second movable lens group must move so that both lens groups will produce an in-focus image of an object at a specified distance, third computing means responsive to the correction signal and the third signal for generating and storing a fourth signal for the second movable lens group; sensing means for producing additional information signals relating to the actual positions of said lens groups, a central processor unit responsive to the first, fourth and additional signals for producing two error signals corresponding to any discrepancy between the actual positions of said lens groups and the positions represented by said first and fourth signals respectively, and means responsive to said error signals for moving the lens groups respectively to positions corresponding to said first and fourth signals.

Growing community of inventors

Stevenage, United Kingdom

Ronald C Wainwright