A physicist wishes to deposit a thin film on both sides of a glass (with index of refraction 1.50) window to reduce reflected light of wavelength 532nm to 0%(adsbygoogle = window.adsbygoogle || []).push({});

In order to achieve 100% destructive interference for light reflectedo ff of the air /thing film inteference and the light reflected off the thin film/glass interface what must hte index of refraction of the thin film be??

so its is purely destructive

[tex] 2d + \frac{1}{2} \lambda = (m+ \frac{1}{2}) \frac{\lambda}{n} [/tex]

what is the value of m though?? So would i assume m=0?? But then what is the value of the thickness?? Sincei want to find the index of refraction ,n.

Perhaps the subsequent sub questions have somethin to do with this answer?

Sketch a graph of the reflected intensity for lambda = 532nm as a function of thickness T 0<T<2000 nm

I could do this if i knew the index of refraction...

What thickness of a film will give this 100% AR effect at 532nm?

What fraction of light at twice the laser wavelength lambda = 1264nm will be reflected from this AR coated window?

P.S. Dont ask me what AR is, i dont know either!

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# Homework Help: Thin film interference

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