# lens equation

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.