US Patent 11698550 Composite lens system with changeable focal length

A composite lens system may include one or more first optical elements configured to provide a first focal length selected from a first continuous range of focal lengths, as well as one or more second optical elements configured to provide a discrete focal length selected from a plurality of discrete focal lengths. The one or more first optical elements and the one or more second optical elements may be configured in series such that the composite lens system provides an output focal length based on a combination of the selected first focal length and the selected discrete focal length.