Mid-infrared LEDs versus thermal emitters in IR dynamic scene simulation devices

摘要

In a radical departure from conventional thermal emitter-based dynamic IR scene simulation devices, we have tested InAsSbP/InAs LEDs grown by liquid phase epitaxy and tuned at several peak-emitting wavelengths inside the mid-IR band. Light uniformity, radiation apparent temperature (T_a), thermal resistance, and self heating details were characterized at T=300° K in the microscale by calibrated infrared cameras in the 3-5 μm (light pattern) and 8-12 μm (heat pattern) bands. We show that LEDs are capable of simulating very hot (T_a ≥740° K) targets as well as cold objects and low observable with respect to a particular background. We resume that cost effective LEDs enable a platform for photonic scene projection devices able to compete with thermal microemitter MEMS technology in testing and stimulating very high-speed infrared sensors used for military and commercial applications. Proposals on how to further increase LEDs performance are given.