Snell’s Law

􀂙Fundamental principle of
light
􀁽 when it strikes the interface
between two transparent
mediums, a portion of the
light is reflected back into
the first medium and a
portion is transmitted into
the second
􀂙Snell’s Law - predicts the
path of light rays as they
travel between media


Index of Refraction [IOR]
􀁽 Determines the amount of bending that light
undergoes when entering a different medium
􀁽 if the media is more dense waves will bend
towards the normal
􀁽 if the media is less dense waves will bend
away from the normal


Light enters a medium whose index of
refraction is less than the medium from
which it exits will refract away from the
normal
􀁽 unless
􀂃 the angle of incidence exceeds the critical angle