Reflection Planar Mirror

The angle of incidence equals the angle of reflection. Angles are measured to the normal (the dotted line) not the surface of the mirror.

The image is imaginary.
Image appears in the mirror, and is the same distance in the mirror as the object is from the mirror.

For diagram which show the Law of Reflection, Image formation in a plane mirror and ray convergence in a concave mirror Click Here
All slides is courtesy of Ohio State University; home of the Buckeyes & maybe this year they will beat Michigan.

Reflection Curved Mirrors

For a concave mirror.

Object	Image
at infinity	a single point at F
beyond C	real, inverted, smaller, between F and C
at C	real, inverted, same size, at C
between C and F	real, inverted, larger, beyond C
at F	no image; parallel rays
close than F	virtual, erect, larger, other side of mirror

For a convex mirror.

Object	Image
at infinity	a single point at F (on other side of mirror)
closer than infinity	virtual, erect, smaller, other side of mirror

For Ohio State slide presentation Click Here

Refraction Thin Lenses

Refraction is the bending of light when the ray passes from a medium of one optical density to another medium of a different optical density. The measure of optical density is related to the index of refraction (n_i).

In this diagram n₂ > n₁

The following table gives types of converging lenses.

object position	image position
at infinity	a single point at F
beyond 2F	real, inverted, smaller, between F and 2F
at 2F	real, inverted, same size, at 2F
between 2F and F	real, inverted, larger, beyond 2F
at F	no image; parallel rays
close than F	virtual, erect, larger, on same side of lens

The following table gives types of diverging lenses.

object position	image position
at infinity	a single point at F on same side of lens
closer than infinity	virtual, erect, smaller, on same side of lens

Two slides to view, both courtesy of Ohio State

A Lens summary in diagrams Click Here
A Lens summary with equations Click Here