Photonic lantern wavefront sensors for optical metrology and aberration control (Invited Paper)

Photonic lanterns are a powerful emerging technology with critical applications in wavefront sensing, ultra-resolution hyperspectral imaging, telecommunications, adaptive optics for deep turbulence, LIDAR, directed energy, and astronomical investigations of extrasolar planets. A photonic lantern is a monolithic optical fiber device consisting of a smooth, continuous 3-D waveguide transition that implements spatial transformations. The lantern effectively decomposes the input light into eigenmodes of the lantern, with each mode corresponding to an output SMF. Thus, we can measure the distribution of intensities among the output single-mode beams to reconstruct the incoming optical field. Our group has pushed lanterns to high coupling efficiencies, with demonstrated broadband (400-700nm) transmission >91%, with efficiency rising to >97% for wavelengths approaching 1000nm and beyond. A rapidly expanding application of photonic lanterns is in the area of wavefront sensing. We will present our recent developments for Photonic Lantern WaveFront Sensors (PLWFS), with particular emphasis on their potential applications for optical system metrology and aberration control.