A promising source of radiation for high-speed optical measuring systems are LEDs capable of operating at significantly high currents compared to nominal ones with a short duration of periodic pulse overloads. Recently, it has become possible to replace laser lighting systems with LED ones in some cases, which significantly reduces the cost of physical experiment and simplifies optical measurements. This work is devoted to the development of an infrared illuminator with an LED for high-speed optical studies of gas-liquid flows. An electrical control circuit for an LED, based on an adjustable pulsed voltage source with preliminary automatic power calibration, is described and the results of measuring the main electrical characteristics of the LED are presented. When the illuminator is overloaded by 70 % in power, the illumination from it increases by 48 %. This illuminator has been tested in a number of thermos-physical experiments to study the dispersion composition of particles from a central nozzle, etc., as well as in a tomographic experiment to measure the velocity of particles in the air flowing around the quadcopter. The results obtained confirmed the effectiveness and prospects of using pulsed illuminators with an LED light source in high-speed optical experiments. 1. Boyko, V.M., Orishich, A.M., Pavlov, A.A., Pikalov, V.V. Methods of optical diagnostics in an aero-physical experiment: monograph / Ed. by V.M. Fomin. Novosibirsk: NSU Publishing House, 2009. 450 p. (in Russian)
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• pulsed LED illuminator
• optical flow diagnostics
• overload LED mode