A compact case for an Michelson interferometer, to be used in the homodyne regime. Currently testing the 3D printed version (PLA with 100% infil), have achieved sensitivity of 10e-14 m/sqrt(Hz). The mirror in the local oscillator arm is connected to a piezo and slides on a smooth rod parallel to the beam insuring proper reflection angle independent of movement. The quarterwaveplates are easy to adjust and lock in via a screw. The adjustable mount, to hold the membrane, is used to match the two beams.
Design to be tested also in vacuum, with a sensitive membrane in one arm to act as a force sensor (KWISP). Due to 3D printed plastic parts (atleast those made with FDM printers) tendency to outgass badly in vacuum (despite 100% infil), the part will also be machined in aluminium.
Piezo attachment and arm length equalizing still needs to be simplified.