A document discusses a “solutionassisted contacting” technique for optical contacting. An optic of surface flatness Lambda/20 was successfully contacted with one of “moderate” surface quality, or Lambda/4. Optics used were both ultra-low expansion (ULE) glass (Lambda/4 and Lambda/20) and fused silica (Lambda/20).

A stainless steel template of the intended interferometer layout was designed and constructed with three contact points per optic. The contact points were all on a common side of the template. The entire contacting jig was tilted at about 30°. Thus, when the isopropanol was applied, each optic slid due to gravity, resting on the contact points.

All of the contacting was performed in a relatively dusty laboratory. A number of successful contacts were achieved where up to two or three visible pieces of dust could be seen. These were clearly visible due to refraction patterns between the optic and bench. On a number of optics, the final step of dropping isopropyl between the surfaces was repeated until a successful contact was achieved.

The new procedures realized in this work represent a simplification for optical contacting in the laboratory. They will both save time and money spent during the contacting process, and research and development phases. The techniques outlined are suitable for laboratory experiments, research, and initial development stages.

This work was done by Glenn De Vine, Brent Ware, Danielle M. Wuchenich, Robert E. Spero, William M. Klipstein, and Kirk McKenzie of Caltech for NASA’s Jet Propulsion Laboratory. NPO-47963