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## Main Question or Discussion Point

So my book has an equation describing the wavelengths of light that are diffracted by a chiral nematic liquid crystal in terms of the refractive index (n), the pitch of the helix (p), and the angle (θ) with respect to the surface. The equation is this -

λ = np√((1-cos

If this isn't clear, inside the square root is (1-cos

λ = np√((1-cos

^{2}θ)/n^{2})If this isn't clear, inside the square root is (1-cos

^{2}θ) divided by n^{2}. But isn't this whole expression the same as p*sinθ? I would think the top of the square root would equal sin^{2}θ, then with the square root the n's would cancel. But this would mean that the wavelength doesn't depend on the diffraction index at all. Am I doing something dumb here?