A Fast and Robust Method of Focusing

In the measuring technology of microscopy, in order to realize high focusing accuracy and also strong noise suppression, the author approves a new focusing method for microscopy on the base of principle of microscope imaging and focus. The method uses Canny algorithm to recognize the edge of the measured object. When the edge of the measured object is the narrowest, the microscope gets the best focusing. The experiment shows that compared with the classical focusing evaluation function, this method is characteristic of unimodality, accuracy, sensibility and noise immunity. The method is an autofucusing method with combination property, and it is especially suitable for high precision and speed microscopic measurement.