Delfa used laser interferometer to measure surface figure of lens or windows, which instrument was imported from Fujinon of Japan. The center wavelength 635nm semiconductor laser is the light source of the interferometer, which can measure the surface accuracy below dia.30mm for plane surface or spherical surface.

The laser interferometer using a small design, which measurement method has property of simple, high accuracy and so on. The Fujinon laser interferometer be used to optimizing the quality inspection system of Delfa and improving the quality of products.