M. Haldun Ozaktas, Zeev Zalevsky and M. Alper Kutay, “The fractional Fourier transform with applications in optics and signal processing,” JOHN WILEY & SONS, LTD, New York, 2001.
The discrete fractional Fourier transform is defined by Zeev Zalevsky in
The company is developing a new physical lens for EDOF.