The PISA Prototype
The first two pictures show the actual interferometer (or the optical element) of the PISA prototype and the very first spectrum that was recorded with this prototype.
The POSA Breadboard
The heart of the POSA is a unique double-beam high-resolution interferometer, consisting of basically a special prism-roof mirror (1), a double-dove prism (2), a beamsplitter (4) and two prism-roof end mirrors (3).
First version of the POSA breadboard with a special prism-roof mirror
The interferometer breadboard has been build in two versions, once with the special prism-roof mirror and in a second version with two hollow roof mirrors replacing the special prism-roof mirrors.
Second version of the POSA breadboard with a two hollow roof mirrors
Because of the optical complexity, the breadboards are difficult to align. The alignment possibilities of the beam-splitter and the roof-prisms will thus be elaborated in the future. First interferogramms have been measured and the optimizations of the breadboards is under way.
