Patent ID: 9140887
Filing Date: 2015-09-22
Classification: G02B

Abstract:
1. A microscope system for observing a state of a surface of an observing target, the microscope system comprising: a light source for emitting a light; a light receiving element; an optical system for irradiating the light emitted from the light source on the observing target while collecting the light, and guiding the light irradiated on the observing target to the light receiving element; a pixel data output unit for outputting pixel data corresponding to a plurality of pixels based on an output signal of the light receiving element; and a control unit for setting a sensitivity parameter for adjusting a value of the pixel data by controlling gain of the light receiving element, and moving a focus of the optical system relative to the surface of the observing target to a plurality of positions in an optical axis direction of the optical system; wherein the control unit calculates an evaluation value using a value of the pixel data corresponding to a predetermined number of pixels of the pixel data output from the pixel data output unit at each position of the focus of the optical system, assumes the calculated evaluation value as the evaluation value corresponding to the position if the calculated evaluation value is within a range between an upper limit value defined in advance and a lower limit value defined in advance, reduces the gain of the light receiving element so that the calculated evaluation value is within the range if the calculated evaluation value reaches the upper limit value, corrects the evaluation value calculated at each position of the focus of the optical system based on a number of reductions of the gain of the light receiving element after reducing the gain of the light receiving element according to the reduction of the gain of the light receiving element to have the corrected evaluation value as the evaluation value corresponding to each position, and detects the position of the focus of the optical system indicating a peak value in a distribution of a plurality of evaluation values corresponding to the plurality of positions of the focus of the optical system and sets the gain of the light receiving element automatically, wherein the control unit moves the focus of the optical system to the position of the focus indicating the peak value and searches an upper limit position and a lower limit position by moving the focus of the optical system in one direction of the Z direction while carrying out the gain adjustment of the light receiving element and sets the upper limit position and lower limit position with the adjusted gain of the light receiving element.