Abstract: An apparatus for measuring visual performance suitable for carrying out various visual functionality tests in controlled and variable opening conditions of the pupils of a subject. The apparatus uses optic systems for the control of ambient brightness, and uses systems of illumination, observation, and measurement of the pupillary dimensions.

Abstract: A device for automatically positioning and centering the optical head of a microscope, for example for surgical use, the optical head being connected to a drive unit. This device analyzes the image framed by the microscope objective by use of an automatic system for analyzing the image light distribution, for example a video camera connected to a processing circuit and possibly to a microprocessor, then processes the image until a reference point of the light distribution is identified by dividing the image into N subzones. Then, on the basis of information regarding the position of the reference point, the device controls the drive unit of the microscope optical head to return the reference point to within a predetermined tolerance zone, if possible.