Patent ID: 6495794
Filing Date: 2002-12-17
Classification: B23K,B29C,G05B,Y02P

Abstract:
A method for producing a three-dimensional article, the steps comprising:a) providing a laser system having a predetermined operating wavelength, a predetermined pulse repetition rate, and a predetermined power output and comprising an expanding, focusing subsystem for providing a dilated, focused laser beam at said predetermined operating wavelength; b) providing a piece of transparent material having a width, a height and a length, said material being substantially transmissive to electromagnetic energy at said predetermined operating wavelength; c) providing manipulation means releasably coupled to said piece of transparent material to move said transparent material in a direction corresponding to at least one of the group: X-axis, Y-axis and Z-axis, said movement being responsive to a control signal adapted to place at least one interior point within said transparent material at a focal point of said dilated, focused laser beam; d) providing a control signal representative of a predetermined three-dimensional shape; e) selectively operating said laser to trace only the surface outline of said predetermined, three-dimensional shape at an interior region of said transparent material as said transparent material is moved in response to said control signal, and wherein said laser beam has a first expanded section with a first beam intensity with a low absorption rate which is transparent to the material, for permeating the material without causing physical changes, and said laser beam subsequently tapering into a focused spot having a second beam intensity with a high absorption rate sufficient enough to cause physical changes, such as cutting; whereby as said transparent material is moved past the focal point of said laser beam, said predetermined, three-dimensional shape is defined within an interior region thereof and substantially totally separated therefrom.