Original Publication Date: 1978-May-01
Included in the Prior Art Database: 2005-Feb-20
Spectrophotometers based upon the use of a rotary interference filter as a dispersive element, such as shown in U. S. Patent 3,751,643, may be calibrated using a thin native pure silicon wafer and a silicon-oxide film wafer. The pure wafer serves as a reflectant standard. The silicon-oxide film wafer generates a wave series when polychromatic light, normal to the plane of the wafer, impinges on its surface. The wave series produces peaks and valleys at known wavelengths which can be used to calibrate the interference filter so as to correlate the angular displacement thereof relative to wavelength. Shown in the drawing is a simple and easy-to-use calibrator 1 useful in the calibration process.