Microscopy with self-reconstructing beams

November 2011

Fahrbach FO, Simon P, Rohrbach A

Nature Photonics 4, 11, 780-785

Nature Photonics   online article

Although self-reconstructing beams have been in the focus of many scientific studies over the past decade, hardly anything is known about their propagation and self-healing behavior in a three-dimensional, inhomogeneous medium. The controlled reduction of scattering and beam spreading would enable a new illumination concept for light microscopes, especially for those designed to look deep into scattering tissue. We show that inside three different classes of refractive index inhomogeneity, i.e. two large glass spheres, a cluster of smaller spheres and a piece of human skin, beam self-reconstruction is indeed possible. We demonstrate that a Bessel beam is unexpectedly robust against deflection at objects, and we define measures for self-reconstruction in this context. We present a prototype of a Microscope with Self-Reconstructing Beams (MISERB) and show that a holographically shaped, scanned Bessel beam reduces scattering artifacts and at the same time increases image quality and penetration depth in dense media.