What is the angular spread of the beam after passing through the prism?

A narrow beam of light with wavelength from 450nm to 700nm is incident perpendicular to one face of a 32,00 degree prism made of crown glass, for which the index of refraction ranges from n=1.522 to n=1.517 for those wavelength. What is the angular spread of the beam after passing through the prism?

I’ve tried working with snells law as well as the prisms equation anf then subtracting exiting ray angles, but I’m not gettting the correct answer, any help would be greatly appreciated.

2 Answers

  • φ’1 = arcsin[sin32°*1.522] = 53.7589°

    φ’2 = arcsin[sin32°*1.517] = 53.5029°

    Sa = φ’1 – φ’2 = .256°

    Final answer

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