Ultrahigh-Speed Optical Processing Using Space-Time Duality

For decades, researchers have explored how to use light to process information. The intriguing reasons for taking this approach are the potential that light has for achieving high bandwidth and integration with high-speed optical communication systems. Optical processing in free space is a mature field that is based on the interplay between diffraction and optical elements such as lenses, apertures and prisms. This area of research has been called Fourier optics, since, by suitably combining diffraction and lenses, one can perform imaging and magnification as well as generate the spatial Fourier transform of objects, which enables filtering, image processing and pattern recognition.