VODCA

Full testbed name

Vortex Optical Demonstrator for Coronagraphic Applications (VODCA)

Managing institution

Space science, Technologies, and Astrophysics Research (STAR) Institute, University of Liège

Main scientific focus

The prime purpose of VODCA is to test and validate manufactured infrared vortex phase masks (and in particular Annular Groove Phase Masks) at the appropriate wavelengths: near- to mid- infrared corresponding to the H, K, L and M bands (1.5 to 4.6 um).

Environment of the testbed

VODCA is located in a ISO 7 clean room (class 10000). The optical bench sits on an active vibration isolation system.

Key hardware items

• supercontinuum laser source delivering single-mode broadband beam from approx. 1.5 to 4 um.

• infrared InSb camera from FLIR, cooled to 77K and operating in the 1.5-5.5um wavelength range

• ALPAO deformable mirror with 97 actuators

• QCL laser producing a single-mode narrow-line emission at around 4.6 um

Current status

In operation. The bench allows to reach the intrinsic on-axis rejection limit of the manufactured Annular Groove Phase Masks (up to a few 1000:1 in broad L-band).

Future of the bench: 1) testing of newly manufactured AGPM, 2) new apodization and wavefront sensing techniques, 3) charge 4 and beyond vortices testing.