Light reflectivity and transmission testing apparatus and method

摘要

Apparatus and method for testing an optical element sample such as a mirror simultaneously and substantially instantaneously both for the total amount of light reflected from and the total amount of light transmitted by a predetermined area of that sample. The apparatus includes a pair of axially aligned light-integrating spheres between which is clamped the test sample so that no light enters or escapes from either sphere. A preferably optically regulated, substantially collimated beam of light is directed through one sphere against the test sample at an angle to the sphere axis. Silicon photo-voltaic light sensitive detectors connected to amplified readout units indicate the total light reflectivity in one sphere and the total light transmission to the other sphere. The method includes directing a light beam against a test sample area at an angle other than normal to the surface of said sample area, simultaneously detecting the total amounts of reflected and transmitted light for the test sample area with light-integrating means, and indicating the detected total amounts of reflected and transmitted light.