Lens positioning system

TLDR: In this article, the authors describe a method to position a lens system of an optical device with a precision of at least 1 μm using read-out circuits using double-correlated sampling structures.

Abstract: Systems and methods to position most precisely a lens system of an optical device are disclosed. Embodiments of these electrical sensors comprise capacitive sensors, inductive sensors and resistive sensors to measure the actual position of a lens system with a precision of at least 1 μm. Read-out circuits using double-correlated sampling structures are providing the position signals from the electrical sensors to a controller. The controller compares the actual position signals with a set-signal representing a target position of the lens signal and issues a signal to a motor to get the lens system moved to the target position. A variety of motors/actuators can be used to move a slider carrying the lens system to the position desired.