Speckle-free Signal Reconstruction with Non-periodic Diffractive Elements on Liquid-crystal SLM

Abstract

The methods to generate intensity signals using diffractive elements bear importance for optical signal processing and printing applications. In principle, the diffractive element (DE) can be viewed as optical memory carrying encoded information about a signal wave s(x), x ∈ ℝ2, which can be generated in a certain output plane by illuminating the DE with a specified wavefront. The capability to generate a certain signal wave, defined in a signal window, is called the optical function of a DE. On one hand, a DE can be implemented as a passive optical component with a fixed optical function. Modern spatial light modulator (SLM) technology on the other hand allows adaptive implementations, where a computer addresses the optical device. The advantage is that the optical function of the DE can be changed with time. For this reason SLMs have a key role in the design of programmable opto-electronic devices for signal generation and processing.