This commend exports 3D objects in the unified view or active layer to .fbx format. This format may provide better results than the older 3DS file format.
To export an FBX file:
Select File > Export > Export FBX (3D only).
The Export FBX Options dialog box opens. Specify the parameters and click Export.
► Click to show/hide the parameters.
Specify the export file name and destination, and then click Save.