Laser "cross-hair" sidelight.
A technique is described for forming an optical laser cross-hair image for use as a radiotherapy sidelight. The technique is developed from a concept introduced earlier by which a line image is formed from a laser beam using a cylindrical lens. By using two cylindrical lenses and appropriate reflectors, two line images can be made to form a cross.
D006801:Humans; D007834:Lasers; D008961:Models, Structural; D011878:Radiotherapy / Q000295:instrumentation* / Q000379:methods; D013679:Technology, Radiologic