Cantilever displacement detection apparatus

摘要

A cantilever displacement detection apparatus comprises a laser diode for emitting a laser beam functioning as detection beam for displacement detection based on an optical lever method, and a position sensor having two light receiving regions for outputting signals corresponding to the intensity of received light. The laser diode and the position sensor are arranged such that the light beam is passed through an objective lens and made incident slantingly on a mirror provided on a free-end portion of a cantilever and the laser beam reflected by the mirror is passed through the objective lens and made incident on the position sensor.