October 2009
Intermediate to advanced
503 pages
14h 28m
English
According to Rayleigh’s criterion, two nearby images are said to be resolved if they are separated by at least a certain minimum distance so that the position of diffraction central maximum of the first image coincides with the first diffracted minimum of the second image in any order of diffraction and vice versa.
Rayleigh’s criterion can be explained by considering the diffraction patterns due to two spectral lines of wave lengths λ1 and λ2. Let A and B represent central maxima of diffraction patterns corresponding to wave lengths and λ1 and λ2. As shown in fig 19(a), the diffraction angle for the central maximum of the image B is larger than the diffraction angle for the central minimum of the ...