A comparison between the measured (solid dots) and theoretical (red line) Fraunhofer diffraction pattern from (a) a printed grating with a 10 μm periodicity, (b) a printed grating with a 25 μm periodicity and (c) a printed grating with a 50 μm periodicity. The data were taken with a red HeNe laser (λ = 632.8 nm). Both the data and theory have been normalized to unity