# Is it possible to bend/refract light 180° using glass sheets of different refractive index?

If possible, How many combination between the numbers of the different layers and the thickness of each layer will give me 180° refraction.

• What are your ideas about an answer to you problem? – Farcher Jan 22 '17 at 5:34
• what type of glass? – user140434 Jan 22 '17 at 5:37
• That looks like 180° not 360° – John Rennie Jan 22 '17 at 6:34
• But you get 360 from two sets back to back. White layers on the outside, black on the inside. – mmesser314 Jan 22 '17 at 7:03
• Do you mean to describe a dichroic mirror? That isn't done exactly by refraction, rather by wavelength-dependent multiple reflections. – Whit3rd Jan 22 '17 at 7:23

$$\theta_i \gt \arcsin\left(\frac{n_2}{n_1}\right)$$