An optical system for measuring surface shapes for radiotherapy planning. 
A system which uses two remote cameras to obtain surface contours for radiotherapy patients is described.  Two variants are presented: one which requires couch movement to obtain multiple outlines, and one utilizing a special illumination method to achieve multiple outlines from one image per camera.  In addition, a technique is discussed in which the grey-scale information from the skin surface (e.g., skin marks placed by the radiotherapist) may be utilized in displaying three-dimensional surface information.  The system may also be used to monitor patient position in real time during each treatment.