A straight line that originates at some point is called a ray. The part of optics dealing with the ray aspect of light is called geometric optics. Light can travel in three ways from a source to anoth...A straight line that originates at some point is called a ray. The part of optics dealing with the ray aspect of light is called geometric optics. Light can travel in three ways from a source to another location: (1) directly from the source through empty space; (2) through various media; (3) after being reflected from a mirror.
