TECHNIQUE FOR MEASURING GRATING FREQUENCY

Experimentally the real and imaginary parts of the Fourier spectrum ar e separated and used to detect the nature of the object, i.e., whether the object is an odd or even function or a combination of both. A mod ified Twyman-Green setup is used for this purpose. This type of splitt ing of the object function into even and odd parts may become useful i n different fields of image processing. As an application the same tec hnique is used for accurate measurement of the grating frequency.