I know one can find the "near field" length of an illuminated diffraction grating by calculating the Talbot Length, but I also know this is not the complete story. What happens when you have instead a light source (like a laser beam) that coherently illuminates a certain number of grating bars/slits , say 8 or 9 open slits. How would one calculate the length of the near field then? it seems that the near field length would increase with the number of slits you coherently illuminate.(adsbygoogle = window.adsbygoogle || []).push({});

Can someone provide me with a better equation or method for finding the near field length?

Thanks in advance

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# Near field of a diffraction grating?

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