Warped Time Stretch: Photonic Hardware Accelerators for Imaging and Sensing
Photonic time stretch is a well-established real-time optical technology. Using dispersion, the spectral modulation of a broadband optical pulse is stretched to alleviate the bandwidth bottleneck present in the subsequent analog-to-digital conversion and digital processing.
The recent warped time stretch generalizes this concept with tailored non-uniform dispersion profiles, reshaping the wideband optical information arbitrarily and in real-time. The approach provides a design pathway for translating a-priori knowledge of signal spectra into context-optimized data acquisition and processing. This has wide-ranging applicability, including optical pulse reshaping, feature extraction, network coding, data compression and optical phase retrieval.
Here, we will analyze the effects of an arbitrary dispersion profile on wideband optical signals, and show how its proper design provides full-field control over critical parameters, e.g. time-bandwidth product, SNR etc. We first show some theoretical results, then apply the warped stretch framework to digital image compression. Finally, we demonstrate a physical implementation of large and reconfigurable dispersion.