Wavelength scanning interferometer and method for aspheric surface measurement

摘要

The present invention discloses a wavelength scanning interferometer and a method for an aspheric surface measurement. The wavelength scanning interferometer comprises a set of tunable lasers (7) used as a light source, a Twyman-Green interferometer used for generating interference fringes, a translation platform (1) used for scanning an optical path difference along an optical axis, an image card (11) used for converting interference data to a digital signal and transmitting the digital signal to a computer (12), and a data card (13) used for synchronizing the actions of a CCD camera (9) and the translation platform (1). Different from the traditional aspheric surface measurement method, the interferometer is capable of measuring a surface with a high aspheric surface degree or a wavefront, and without the need of a zero compensation mirror. In addition, the method does not need a complex and usually expensive multi-dimensional movement platform.