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fsonnichsen
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- TL;DR Summary
- How do blazed gratings improve efficiency in spectrometer
I cannot for the life of me find any concise information on how blazed gratings improve the spectral throughput of a spectrometer system. The blazed grating structure and how it redirects spectral reflection is itself understandable- but any information I have indicates that it somehow "concentrates" the diffracted light energy into a higher order spectrum. What I see is that the specular output is indeed reflected away from the m=0 order, but beyond this I do not see how the specular content leads to an enhanced diffraction/ spectrum. In fact it would seem as those this light would obscure the higher order into which it is reflected.
I have consulted the ubiquitous Born & Wolfe on this (no information at all!), Hecht (meager information with no mathematical analysis) and Jenkins & white, not to mention a half dozen books on spectrometers. All simply state that the blaze, when mounted at the Littrow angle for the wavelength, mysteriously enhances the signal. I need the math here, or at least a ray-trace sketch to figure out how this happens.
I am trying to track down the 1916 paper by Wood and Trowbridge but meantime does anyone know a textbook (or even an online white paper) working through this problem?
Thanks
Fritz
I have consulted the ubiquitous Born & Wolfe on this (no information at all!), Hecht (meager information with no mathematical analysis) and Jenkins & white, not to mention a half dozen books on spectrometers. All simply state that the blaze, when mounted at the Littrow angle for the wavelength, mysteriously enhances the signal. I need the math here, or at least a ray-trace sketch to figure out how this happens.
I am trying to track down the 1916 paper by Wood and Trowbridge but meantime does anyone know a textbook (or even an online white paper) working through this problem?
Thanks
Fritz