Optical Comparators

There are several bulbs available for the optical comparators. The older units used a 12 Volt 100 Watt bulb for the projection and the same for the surface. These bulbs are built in reflector type of bulbs (cone shaped). Both optical comparator bulbs would be located inside the case of the machine with fiber optic cables bringing the light to the lamp house that points toward the machine for profile lighting and another fiber optic cable that splits into two and brings light to either side of the lens for surface lighting. These point toward the operator.

On the newer optical comparators there is one 24 volt 150 watt bulb (no reflector, shaped like your finger) in the top of the lamp house (no fiber optic cable) and one 24 Volt 250 watt bulb (reflector type, cone shaped) in the bottom of the lamp house. This fiber optic cable splits into two and brings light to either side of the lens for surface lighting. These point toward the operator.

Optical comparator surface illumination

Picture above shows optical comparator with surface illumination. Optical comparator is made by Dorsey Metrology, model 16H.

Optical comparator thread inspection

Picture above shows typical application of optical comparators – thread inspections. Optical comparator is made by Dorsey Metrology, model 16H with optional surface illumination (not switched on in photo) and precision fixture with 2.12″ jaw opening.