About us - lcoptical.com We have established a complete system for outgoing parts inspection that includes optical metrology such as ZYGO white-light interferometer, Zygo GPI Interferometers, Perkin-Elmer … We have established a complete system for outgoing parts inspection that includes optical metrology such as ZYGO white-light interferometer, Zygo GPI Interferometers, Perkin-Elmer …