Stray Light in Monochromators

I iire2.14, Htst-ttdseoond-ofder Affnedon offs diffraction gnl-ing. The lepon where there is no overlap of the first- and second-order d fraclioa is called the free spectral range. 

TaUe 2.1. Wavelengths and Rehthre Intensities of Mcroiry lines  

In this case the monochromator is generally returned to the manufacturer for realignment. 

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