Most of the different approaches proposed in the literature need to measure both amplitude and phase of the scattered fields. As a matter of fact, in several areas of applied science, the phase distribution of the scattered fields is often too corrupted by noise to be useful, or there is no phase measurement at all. Even if there is some effort nowadays to provide experimental setups capable of measuring all the components of the scattered fields, it is of great importance to develop approaches that image samples from only amplitude data, as these latter would open the way to simpler and cost effective experimental setups. In this respect, different phaseless strategies have been introduced by LEMMA’s researchers and tested in different scenarios, also involved experimental data. As detailed in the following papers, LEMMA’s researchers have introduced both a one-step procedure [4],[5], wherein the intensity-only data are exploited in a minimization scheme thanks to a proper definition of the cost functional, as well as a two-step procedure [1],[2], wherein the complex scattered fields embedded in the available data are retrieved first and then a traditional inverse scattering problem is solved. Finally, a three steps imaging technique which exploits only amplitude measurements of both the total and incident fields is discussed in [3].

  1. L. Crocco, M. D’Urso, and T. Isernia, “Inverse scattering from phaseless measurements of the total field on a closed curve,” JOSA A  vol. 21, pp. 622-631, 2004. [click here]
  2. O. M.Bucci, L. Crocco, M. D’Urso, and T. Isernia, “Inverse scattering from phaseless measurements of the total field on open lines,” JOSA A  vol. 23, pp. 2566-2577, 2006. [click here
  3. L. Crocco, M. D’Urso, and T. Isernia, “Faithful non-linear imaging from only-amplitude measurements of incident and total fields,” Optics Express, vol. 15, pp. 3804-3815, 2007. [click here
  4. M. D’Urso, K. Belkebir, L. Crocco, T. Isernia, and A. Litman, “Phaseless imaging with experimental data: facts and challenges,” JOSA A, vol. 25, pp. 271-281, 2008. [click here
  5. L. Crocco, M. D’Urso, and T. Isernia, “Quantitative imaging from diffracted fields intensities: an inversion method and its experimental validation,” Journal of Modern Optics, vol. 57, no. 9, pp. 777-782, 2010. [click here]