1. Law of Refraction Ramos, Solomon Bell, Emmanuel

2. Snell’s Law Snell's law states that the ratio of the sines of the angles of incidence and refraction is equivalent to the ratio of phase velocities in the two media, or equivalent to the opposite ratio of the indices of refraction [LEFT] Refraction of light at the interface between two media of different refractive indices, with n2 > n1. Since the velocity is lower in the second medium (v2 < v1), the angle of refraction θ2 is less than the angle of incidence θ1; that is, the ray in the higher-index medium is closer to the normal.

3. The Discovery of Refraction The law of refraction was first accurately described by Ibn Sahl, of Baghdad, in the manuscript On Burning Mirrors and Lenses (984).[7][8] He made use of it to work out the shapes of lenses that focus light with no geometric aberrations, known as anaclastic lenses.[9]

4. Refraction The law of refraction states that the incident ray, the refracted ray, and the normal to the interface, all lie in the same plane. Furthermore, where theta_1 is the angle subtended between the incident ray and the normal to the interface, and theta_2 is the angle subtended between the refracted ray and the normal to the interface. The quantities n_1 and n_2 are termed the refractive indices of media 1 and 2, respectively. Thus, the law of refraction predicts that a light- ray always deviates more towards the normal in the optically denser medium: i.e., the medium with the higher refractive index. Note that n_2>n_1 in the figure. The law of refraction also holds for non-planar interfaces, provided that the normal to the interface at any given point is understood to be the normal to the local tangent plane of the interface at that point.

5. Refraction Definition The refractive index n of a dielectric medium of dielectric constant K.