Microscope automatic focus method of detection and the microscope automatic focus detection device and the microscope null object lens which

摘要

PROBLEM TO BE SOLVED: To provide an automatic focus detector for a microscope capable of realizing high-speed and accurate AF control even when a noise image such as dust exists on a subject image. ;SOLUTION: This focus detector is equipped with a focusing signal output switching means capable of switching an area dividing focusing signal output means(outputting an aimed focusing signal from the focusing state of every division by an area dividing contrast arithmetic means) and an entire range focusing signal output means(outputting the focusing signal by an entire range contrast arithmetic means) according to the amount of the depth of focus of an objective lens 3. In the case the control by an area dividing system is not required according to the amount of the depth of focus of the objective lens, such control is omitted, so that a focusing time is shortened, and the accurate AF control is executed.;COPYRIGHT: (C)1997,JPO