Teaching diffraction and signal processing with a liquid crystal spatial light modulator

In this work we propose the use of a liquid crystal spatial light modulator (LC-SLM) as a useful tool to teach and experience diffraction and signal processing. The LC-SLM acts as a programmable pixelated diffractive mask. The Fourier spectra of the image displayed in the LC-SLM is visualized through a simple free propagation diffraction experiment. This optical system allows easily testing different diffractive elements and performing several signal processing experiments. As a demonstration we include experimental results with diffraction gratings, computer generated holograms, diffractive lenses and axicons