Products Optical Measuring Optical Measuring Nikon Metrology Categories Optical Measuring Instruments Nikon Metrology's optical measuring systems include autocollimators, digital height gages, measuring microscopes, optical comparators and software. Measuring microscopes High precision measuring microscopes featuring the latest in digital imaging and industrial metrology technologies. Profile Projectors Profile projector or optical comparator technology is designed to display accurate magnification of workpiece for comparison and precision measurements.