Long sequence single-exposure videography using spatially modulated illumination.

Frequency recognition algorithm for multiple exposures (FRAME) is a single-exposure imaging technique that can be used for ultrafast videography, achieved through rapid illumination with spatially modulated laser pulses. To date, both the limit in sequence length as well as the relation between sequence length and image quality are unknown for FRAME imaging. Investigating these questions requires a flexible optical arrangement that has the capability of reaching significantly longer image sequences than currently available solutions. In this paper we present a new type of FRAME setup that fulfills this criteria. The setup relies only on (i) a diffractive optical element, (ii) an imaging lens and (iii) a digital micromirror device to generate a modulated pulse train with sequence lengths ranging from 2 to 1024 image frames. To the best of the authors' knowledge, this is the highest number of temporally resolved frames imaged in a single-exposure.