ZEMAX imports data from CAD programs via the IGES, STEP, SAT and STL formats, and exports data in the same formats. This allows simple and fast exchange of design data between ZEMAX and mechanical design packages.

However, the quality of exports from CAD programs is very variable, which can lead to problems when objects are imported into ZEMAX. Generally speaking, the tolerances required for optical-precision ray tracing are 100 to 1000 times tighter than typical mechanical tolerances. A little care taken at the export stage can eliminate many common problems on import.