The so called “lens equation” reads

## Solving for focal length

## Solving for distance to object

## Solving for distance to Image

## Interpretation of the lens equation

What can be derived from this formula?

- The Image of infinite distant objects in in the focal plane.

When thenobject moves to infinity (= when the distance_to_object get infinite large), then

Say,

- An object that is at double focal length distance ob object sideis mapped to an image that is in double focal length distance on image side.
- In other words : If we want a 1:1 mappingin distance X so choose

- If the object distance equals the focal length then the image is at infinity.
- The closer an object coming from infinity approaches the focal length, the closer get image distance and focal length. So holds.
- An object in focal length in front of the lens is mapped to infinity on image side.
- For an Object closer to the lens than the focal length holds, say, the image is generated on the object side (!) of the lens.