Coherent and non-coherent interferometry with cold mirror for contact lens thickness measurement

An apparatus for measuring a sample contact lens, the apparatus comprising:

• a housing to hold a sample contact lens to be measured, one or more movement stages coupled to the housing, wherein the two or more movement stages are constrained to linear movement;
• an interferometer and an interferometer probe having a source of infrared light, a source of visible light oriented at an angle with respect to the interferometer probe, a cold mirror capable of reflecting visible light onto the sample contact lens, the cold mirror further capable of transmitting infrared light to the sample lens, and a camera capable of detecting visible light and infrared light.