Abstract

In common-path interferometers both the reference and test beams travel the same path. They have the advantage to be self-referencing, inherently stable and relatively insensitive to vibrations. The phase contrast technique ¹ converts phase distributions into intensity ones. The technique consists in employing a phase disk filter of radius smaller than or equal to the system’s Airy disk placed at the geometrical focal plane of the imaging system. The main problem with this technique is the construction and precise alignment of the filter.

© 2002 Optical Society of America