US Patent 7926993 Projector unit

A projector unit is provided with a mechanism for changing the spatial distribution of a light beam. The projector unit includes a housing, an action element having a revolving shaft, a first diaphragm for cropping the light beam, wherein the first diaphragm is fixedly coupled to the shaft of the action element, a second diaphragm for cropping the light beam, wherein the second diaphragm is rotatingly coupled to the shaft of the action element, a first biasing element disposed between the second diaphragm and the housing, wherein the first biasing element regulates a positioning of the second diaphragm relative to the housing, and a second biasing element disposed between the first diaphragm and the second diaphragm, wherein the second biasing element regulates a spacing between the first biasing element and the second biasing element.