Method and apparatus for aligning optical elements and testing aspheric optical components

An apparatus suitable for adjustably mounting an optical element, the apparatus comprising;

• a mount having a base;
• a mount plate including first and second side surfaces;
• means for securing the mount plate to the base at a known relation thereto;
• and adjusting means for adjusting the orientation of the mount plate relative to the base;
• a generally planar frame suitable for supporting an optical element;
• and
• coupling means for releasably coupling the frame to the mount paste at a known orientation thereto for supporting a second frame for a second optical element in the same alignment as a first frame for a first optical element after the first frame has been released from its coupling to the mount plate wherein the coupling means comprises three, spaced-apart registration assemblies, each registration assembly having:
• a registration sphere rigidly attached to the frame;
• and
• a registration site attached to the mount plate, the registration site suitable for directly mating with the registration sphere, the registration site including:
• a mechanical constraint suitable for mating with the registration sphere;
• and
• a magnet attached to the frame proximate the mechanical constraint, the magnet providing magnetic attraction with the registration sphere such that the frame is releasably coupled to the mount plate when the registration spheres are mated with the mechanical constraints.

A method for testing aspheric optical components with a spherical test beam from an interferometer, the method comprising the steps of:

• providing a prealigned alignment CGH on a first frame;
• providing a prealigned CGH null compensator on a second frame;
• providing an apparatus suitable for adjustably mounting an optical element, the apparatus comprising:
• a mount having a base;
• mount means for removably securing the mount plate to the base at a known relation thereto;
• including means for adjusting the orientation of the mount plate relative to the base;
• and
• a coupling means for releasably and directly coupling the frames to the mount plate at a known orientation the frame includes three registration members, each having a part spherical surface, and the mount plate includes three mechanical constraints for receiving the registration members, the mechanical constraints including a recessed site having a magnet therein providing a force to urge the registration members to seat on the mechanical constraints;
• generating a spherical test beam from the interferometer;
• coupling the alignment CGH to the apparatus;
• diffracting the spherical test beam with the alignment CGH to obtain an interferogram;
• adjusting the mount plate such that the alignment CGH diffracts the test beam onto itself, thereby producing null interference fringes;
• removing the alignment CGH from the apparatus;
• and
• coupling the CGH null compensator to the apparatus such that the spherical test beam is diffracted to form an aspheric wavefront for standard testing of the aspheric components.