Scattering environments complicate imaging because they scramble phase information of an imaging light wave. Since classical imaging approaches rely on this phase information, they fail in the presence of scattering media. Photon time of flight methods that utilize a time varying intensity such as a light pulse or modulated light source don't rely on the light phase and thus can be used to reconstruct images in scattering environments. Using this information one can reconstruct images after reflection off a scattering wall (Non-Line-of Sight Imaging) or after propagation through a scattering medium (Time Resolved Diffuse Tomography). Unfortunately, image reconstruction in time of flight methods has so far relied on principles of inverse rendering and photon diffusion that are entirely different from the wave imaging principles that are common to all other imaging methods, including optical, ultrasound, and RADAR imaging. Virtual Wave imaging is based on the insight that the intensity distribution of intensity modulated light can be modeled as a wave that propagates in the same way a real wave would. Describing scattered light as a virtual propagating wave allows us to use the image formation methods and algorithms that are common to all wave imaging methods. We can also design and interpret measurements using the extensive existing knowledge available in the fields of line of sight optical and wave imaging.

Full-field swept-source optical coherence tomography (OCT) achieves acquisition speeds of about 40 MHz equivalent A-scan rate. At these acquisition rates it no longer suffers from random phase changes caused by sample motion and it can thus be thought of as a truly holographic OCT technique fully capturing amptliude and phase. This not only allows us to perfom advanced post-processing on volumetric OCT data, such as aberration correction, it also enables functional retinal imaging. Using suitable computational approaches, we show that this technique captures function of neurons and receptors of the living human retina. Full-field swept-source OCT might thus become a valuable imaging tool for basic research and medical diagnostics.