METHOD AND APPARATUS FOR
IDENTIFYING SURFACE FEATURES
ASSOCIATED WITH SELECTED LAMINA
OF A THREE-DIMENSIONAL OBJECT
 Inventors: Chris R. Manners, Moorpark; Dennis R. Smalley, Newhall, both of Calif.
 Assignee: 3D Systems, Inc., Valencia, Calif.
 Appl. No.: 08/854,950  Filed: May 13, 1997
 Int. CI.6 B29C 35/08; B29C 41/02;
 U.S. CI 264/401; 264/40.1; 264/308;
364/130; 364/468.27; 425/135; 425/174.4
 Field of Search 264/40.1, 308,
264/401; 425/135, 174.4; 364/468.27, 130
 References Cited
U.S. PATENT DOCUMENTS
5,096,530 3/1992 Cohen 264/401 X
5,182,715 1/1993 Vorgitch .
5,258,146 11/1993 Almquist et al 264/401
5,597,520 1/1997 Smalley .
FOREIGN PATENT DOCUMENTS WO 95/29053 11/1995 WIPO .
Copy of International Search Report for International Application No. PCT/US98/09666.
Primary Examiner—Leo B. Tentoni
Attorney, Agent, or Firm—Dennis R. Smalley; Forrest L. Collins
This invention relates to the stepwise layer-by-layer formation of a three-dimensional object through application of the principles of stereolithography and to the automatic detection of surface features of each layer of a three-dimensional object to manufacture parts more reliably, more accurately and more quickly. Automatic detection of trapped volume regions and size of solidified cross-sectional regions are disclosed. Automatic selection of recoating styles is made based on (1) the detected regions,(2) empirically or otherwise determined optimum recoating styles for different types of regions, and (3) a look-up table, other correlation system, or processor for associating recoating style information with laminae containing particular identified regions.
34 Claims, 26 Drawing Sheets