External linearisation of a MEMS electrothermal scanner with application in a confocal microscope

A compensatory mapping (CM) technique for external linearisation of a MEMS electrothermally actuated optical scanner is reported. Each individual axis of a two-axis MEMS scanner was linearised by the CM technique, and the scanner was then incorporated into a confocal optical microscope configuration. Cross-talk in the scanner when both axes are driven simultaneously, and arising when a drive signal to one axis of the scanner produces a mechanical response in the orthogonal scan axis, was subsequently compensated for by using a look-up-table optimised using a random search algorithm.