A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed...http://www.google.com.au/patents/US4863538?utm_source=gb-gplus-sharePatent US4863538 - Method and apparatus for producing parts by selective sintering
