Development and Characterization of an LED-Based Light Source for High-Speed Schlieren Imaging
This work investigates the viability of using a cost effective, 623 nm light emitting diode (LED) based light source for high-speed schlieren imaging. The pulser circuit used to drive the LED was characterized on the basis of input response, pulse train characteristics, and pulse energies. Relative brightness data was measured with a photodiode and further examined within a schlieren system. Flow images of decaying, cylindrical shocks were obtained with the LED system and benchmarked against a high intensity discharge (HID) lamp. It was found that the LED could be overdriven up to 20 times the rated current while generating down to 100 ns pulses at up to a 1 MHz repetition rate. Moreover, although the LED system produced higher signals and reduced exposure times, similar image detail was observed for each light source. However, the LED exhibited a distinct advantage over the HID lamp in terms of image blur.
Lincoln, D. (2016). Development and Characterization of an LED-Based Light Source for High-Speed Schlieren Imaging (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/25637