While the angular resolution is the obvious driver for pushing instruments in the visible wavelength range, working with short wavelengths comes with challenges. In this presentation I will review the latest developments regarding photonic developments for the recombination of beams in the visible. Photonic devices constitute a promising avenue for the future instrumentation in interferometry, offering compact, stable and potentially complex architectures. Especially in the context of the spectro-interferometer FIRST installed on the SCExAO platform at the Subaru Telescope, we are exploring two different manufacturing technologies producing waveguides with low or high refractive index contrast. I will review the main challenges we are facing, regarding insertion and propagation losses, as well as polarization effects, and introduce current research developments towards visible design for active phase modulation devices, 3D-architectures and photonic lanterns.
|