The important property of prisms in this article is their ability to redirect light through refraction and reflection ... exit the glass above a critical angle. Eventually, prism glass was ...

When a ray of light is incident at normal incidence, (at right ... angle, the ray changes direction as it refracts. The dotted line is the normal (perpendicular) to the surface. In refraction ...

Light is a type ... line drawn at right angles to the surface of the glass block. Angle of incidence i = angle between the incident ray and the normal. Angle of refraction r = angle between ...