A potentially ultrafast optical analog-to-digital (A/D) converter scheme is proposed and was partly studied experimentally. In the A/D converter scheme the input signal controls the wavelength of a diode laser, whose output beam is incident on a grating. The beam from the grating hits a diffractive optical element in an array. The wavelength determines which element is illuminated. Each element fans out a unique spot-pattern bit code to be read out in parallel by individual detectors. In the experiment all patterns but one from 64 array elements were read out correctly.
© 2000 Optical Society of America
Mathias Johansson, Björn Löfving, Sverker Hård, Lars Thylén, Mehran Mokhtari, Urban Westergren, and Costantino Pala, "Study of an Ultrafast Analog-to-Digital Conversion Scheme Based on Diffractive Optics," Appl. Opt. 39, 2881-2887 (2000)