Patent ID: 7813579

Claim:
A microscope system comprises: a light guiding optical system for guiding an optical image of a sample to a focus control optical path used for focus control; focus control image pickup means disposed on the focus control optical path for acquiring a two-dimensional image based on the optical image guided to the focus control optical path; and focus control means for analyzing the image acquired by the focus control image pickup means, and acquiring focus control information when the image of the sample is picked up on the basis of the analysis result, wherein the focus control image pickup means is equipped with first image pickup means designed so that the optical path length in the light guiding optical system varies along a predetermined variation direction within an image pickup face, and disposed at a position corresponding to an image forming plane of the optical image of the sample so as to the cross the image forming plane, and second image pickup means designed so that the optical path length varies along the variation direction and at a different variation rate from the first image pickup means within the image pickup face, and disposed at a position corresponding to an image forming plane of the optical image of the sample so as to cross the image forming plane, and wherein the first image pickup means and the second image pickup means are designed so that the optical path lengths thereof vary along the variation direction in opposite directions to each other, and the focus control means analyzes image contrast variation in the variation direction on the image acquired by the focus control image pickup means, and the focus control information is acquired on the basis of the analysis result of the contrast variation.