Patent ID: 6873473

Claim:
A two position variable focal length lens comprising: a common lens element moveably positioned on an optical axis; a wide angle lens element moveable between a first location removed from the optical axis and a first position on the optical axis on an image side of the common lens element; and a telephoto lens element moveable between a second location removed from the optical axis and a second position on the optical axis on the image side of the common lens element, wherein a magnification ratio change is effected by moving the common lens element along the optical axis and switching between the wide angle lens element located at the first position on the optical axis and the telephoto lens element located at the second position on the optical axis and the two position variable focal length lens satisfies the following condition: |f C −f ZT |<|f C −f ZW |, where f C is a focal length of the common lens element, f ZT is a focal length of the two position variable focal length lens in a telephoto position, and f ZW is a focal length of the two position variable focal length lens in a wide angle position.