Generation of Sinusoidal Light Intensity
Harry Julich · Applied Optics · 1963
An expression is derived for the required shape of an aperture, when a chopper blade rotating over it periodically transmits light through it. Harmonics are inherently low in this scheme; the system is easily constructed and should prove particularly useful in the testing of the many photo and infrared detectors the frequency response of which extends into the ultrasonic region.