Prasanna Rangarajan

A passive method for extending the native contrast range of semiconductor light sources using spectral filters is presented from both a theoretical framework including performance bounds. The approach is experimentally verified.

The Light Scaled Space-Time Bandwidth Product is proposed as a means of quantifying the performance space of Neuromorphic/Event-Based sensors. Inspired by this metric, the sensor is demonstrated to successfully detect vibrating objects behind scattering media.

This work recovers images of voids embedded inside a scattering medium using a tunable laser and a CMOS camera by adapting ideas from intensity interferometry and photon migration through disordered media.

The presence of a scattering medium in the imaging path between an object and an observer is known to severely limit the visual acuity of the imaging system. We present an approach to circumvent the deleterious effects of scattering, by exploiting spectral correlations in scattered wavefronts. Our Synthetic Wavelength Holography (SWH) method is able to recover a holographic representation of hidden targets with sub-mm resolution over a nearly hemispheric angular field of view. The complete object field is recorded within 46 ms, by monitoring the scattered light return in a probe area smaller than 6 cm × 6 cm. This unique combination of attributes opens up a plethora of new Non-Line-of-Sight imaging applications ranging from medical imaging and forensics, to early-warning navigation systems and reconnaissance. Adapting the findings of this work to other wave phenomena will help unlock a wider gamut of applications beyond those envisioned in this paper.

A computational imager combining ideas from correlography and phase retrieval is used to recover images of non-line-of-sight (NLoS) objects. It exploits the intrinsic roughness of real-world surfaces to indirectly illuminate NLoS objects and intercept the return.