An apparatus for depicting contour lines on the surfaces of a model, the apparatus
comprising a bed for supporting the model, and at least one laser for projecting
a plane of light at a predetermine height from the bed. A method of depicting contour
lines on surfaces of a model, the method comprising projecting a plurality of planes
of light in spaced relation over the surface of a support to illuminate contour
lines on objects on the surface that break the planes of light.