Refraction

Refraction

The bending of light as it passes from one medium to another (at an angle other than normal) due to change in velocity

Index of refraction

The ratio of the speed of light in a vacuum over the speed of light in a material

Application

Used to identify gemstone composition

Snell

Found the relationship between indices of refraction and angles as light passes from one material to another

Critical angle

The incident angle, as light passes from a lower velocity (higher index) medium to a faster velocity (lower index) medium that causes light to refract 90 degrees

Total internal reflection

Light trying to pass from a slower velocity/higher index material to a faster velocity/lower index material past the critical angle is reflected

Application of total internal reflection

fiber optics

Converging lens

Lens that brings light rays together (corrects far sightedness)

Diverging lens

Lens that spreads light rays apart (corrects nearsightedness)

Galilean telescope

A telescope with a diverging lens for the eye piece and a converging lens for the objective lens. It produces an upright but slightly distorted image.

Keplerian (refracting lens) telescope

a telescope with a converging lens for both the eye piece and the objective lens. It produces an inverted image

Spherical aberration

Light far from the principle axis doesn't focus at the focal point

Chromatic aberration

Colors have different focal points

Sky color

one reason why the sky is blue is because blue refracts more than red

Mirage

An image that is made when layers of atmosphere close to the earths surface have different temp which cause different indices of refraction