About the cover
Imaging through opaque, light-scattering layers is an important capability in many fields, including nanotechnology and the biosciences. Several promising methods are being developed, but typically involve invasive procedures such a placing a detector or nonlinear material behind the scattering layer. Jacopo Bertolotti et al. now demonstrate a non-invasive imaging procedure that makes use of correlations in the speckled intensity pattern that is produced when laser light passes through a scattering medium. Fluorescent micrometre-sized objects obscured by scattering layers can be imaged by measuring total fluorescence at several different angles of laser incidence and by using an iterative algorithm that disentangles the spatial information of the object and the speckle pattern. The authors successfully construct detailed images of cell-sized fluorescent objects hidden six millimetres behind scattering layers, and a complex biological sample sandwiched between two opaque screens. Cover graphic by Cameron Slayden/Cosmocyte.