PHYWE Diffraction intensity at multiple slits and diffraction grating

Principle Several slits, all of the same width and the same distance from each other, as well as transmission grids with different grid constants, are exposed to laser light. The corresponding diffraction patterns are measured according to their position and intensity using a photodiode that can be biased. Advantages Understand how an optical grating works by approaching it through "many slits" Coherent laser light allows easy observation Clear correlation of the measurement results with the underlying theory Tasks The position of the first intensity minimum due to a single slit is determined and this value is used to calculate the slit width. It is necessary to determine the intensity distribution of the diffraction patterns of a triple, quadruple or even quintuple slit, where all slits have the same width and the same distance from each other. It is necessary to estimate the intensity ratios of the central peaks. For transmission gratings with different grid constants, it is necessary to determine the positions of the peaks of several diffraction orders and use the found value to calculate the wavelength of the laser light. Learning Objectives: Huygens' Law; Interference Law; Fraunhofer and Fresnel Diffraction Law; Coherence Law; Laser Law.