Microscope system, focus position detection method, and focus position detection program

Abstract

To provide a microscope system capable of automatically detecting a position of a focus of an optical system relative to an observing object. A light emitted from a laser light source is irradiated on an observing object, and the light reflected by the observing object is guided to a light receiving element. An evaluation value based on a plurality of pixel data is set so as to be smaller than an output upper limit value Emax and greater than a multiplication value Enof a noise level. The evaluation value is calculated with the set gain while moving the objective lens in an upward direction from a current position zs. The gain is reduced by a constant amount every time the evaluation value reaches the output upper limit value Emax. The position in the Z direction of the objective lens when the evaluation value becomes a peak is detected.