Abstract: A machine vision analysis apparatus and method for automatically checking objects for specified characteristics. A video camera is provided for producing an analog video input signal corresponding to an area having an object therein being observed by the video camera. A video timer and synchronizer is used for coordinating synchronous operation of the machine vision apparatus. A digital-to-analog converter is also provided for converting a digital threshold gray level into an analog threshold level corresponding to said digital threshold level, wherein an upper and a lower threshold level are produced. A comparator is used for digitizing the analog video input signal into a digitized video signal based on the analog threshold gray levels, wherein the video input gray level must fall between the lower threshold gray level and the upper threshold gray level for a pixel to be digitized into an ON state.

Abstract: A pap smear inspection apparatus and method for automated screening of cytological smears for dense, possibly malignant cells includes a specimen slide for receiving a cytological smear and a microscope for enlarging the image of the smear. The microscope is outfitted to receive a video camera for creating an analog video signal corresponding to an area enlarged by the microscope and being observed by the video camea. A video timer synchronizes operation of the smear analysis apparatus. An image window generator focuses the analysis of the apparatus on a sub-area of the entire video image. A converter is provided for converting a digital threshold level into a corresponding analog threshold level. A comparator is used for transforming the analog video input signal into a binary video signal according to the analog threshold levels. A pixel counter sums the number of ON pixels both in the transformed video signal, and within the designated window sub-area of said video signal.