Simultaneous Multiple Timescale Imaging For High-Speed Accelerometry Using The FRAME-Method

Fast transient events, such as the disintegration of liquid bodies or chemical reactions between radical species, involve various processes that may occur at different timescales. Currently, there are two alternatives for monitoring such events: burst- or high-speed imaging. Burst imaging at ultra-high speeds (~ 100 MHz - THz) allows the fastest processes to be captured but only for a narrowly confined period of time and under the condition that the onset can be predicted. To monitor long lasting events with existing high-speed imaging technology, the frame rate must be reduced (~ kHz - 1 MHz) and thus processes occurring on sub-microsecond timescales cannot be observed. To date, no imaging technology is capable of visualizing detailed sub-microsecond dynamics over a long period of time. In this manuscript we present a solution to this technological gap by combining multiplexed imaging with high-speed sensor technology resulting in temporally resolved image series at two simultaneous timescales. We demonstrate its unique capability of tracking structures at MHz burst rates over a long time by, for the first time, extracting 2D accelerometry data acting upon liquid bodies at kHz frame-rates.