In the current issue of Optics Express, there is a focus issue on Astrophotonics. The coordinators, Joss Bland-Hawthorn and Pierre Kern, have an introductory paper, Astrophotonics: a new era for astronomical instruments. The abstract is
Astrophotonics lies at the interface of astronomy and photonics. This burgeoning field has emerged over the past decade in response to the increasing demands of astronomical instrumentation. Early successes include: (i) planar waveguides to combine signals from widely spaced telescopes in stellar interferometry; (ii) frequency combs for ultra-high precision spectroscopy to detect planets around nearby stars; (iii) ultra-broadband fibre Bragg gratings to suppress unwanted background; (iv) photonic lanterns that allow single-mode behaviour within a multimode fibre; (v) planar waveguides to miniaturize astronomical spectrographs; (vi) large mode area fibres to generate artificial stars in the upper atmosphere for adaptive optics correction; (vii) liquid crystal polymers in optical vortex coronographs and adaptive optics systems. Astrophotonics, a field that has already created new photonic capabilities, is now extending its reach down to the Rayleigh scattering limit at ultraviolet wavelengths, and out to mid infrared wavelengths beyond 2500nm.
I think laser guide star should be an important part of Astrophotonics. They mentioned in (vi), but didn’t mention in the main text at all. Also I don’t understand why large mode area fibers are the key to generate artificial stars.
It is a very interesting issue for me, although laser guide star is suprisingly absent.