First Nulling Results with simple ring coronograph

20-06-2021 #

First Nulling Results with simple ring cornagraph #

Thanks to our Intern Yoann Leclerc, we have a first test bench to test at the same time the injection into the IFU with MLA and a fiber, and we have the first nulling results. It is very promising.

Photo of a test bench to mesure Nulls in an single mode IFU
grid of coronagraphic masks

The test bench allowed us to test a grid of ring coronagraphs developped by Jonas Kühn.

The test bench after a painstaking alignement of the fiber to the MLA and to the bench allow to scan the image of the MLA with high resolution (better than 0.1 microns) using a 3 axis stage. It allows to build a coupling map and assess the null achieved. as shown on the next picture

Fiber coupling maps showing the best null achieved for the seven useful spaxels

This figure is made with monochromatic light. We reach the required null levels. There are still many things to understand!