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arXiv · 2602.04483

Passive Incoherent Ultrafast Mid-Infrared Upconversion Imaging and Its Calibration

Jin-Peng Li·Zhi-You Li·Zhao-Qi-Zhi Han·Xiao-Hua Wang·He Zhang·Yin-Hai Li·Bo-Wen Liu·Wen-Tao Luo·Zhi-Yuan Zhou·Bao-Sen Shi
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Abstract

Ultrafast mid-infrared (MIR) imaging is a key enabling capability for monitoring transient thermal and plasma phenomena in scientific diagnostics and industrial safety. However, conventional cryogenic MIR cameras face a fundamental trade-off between frame rate, noise, and pixel format. Here we report a passive, incoherent MIR imaging platform that leverages sum-frequency upconversion in chirped periodically poled lithium niobate (CPLN) to translate broadband 3--5um scenes to the near-infrared, enabling ultrafast acquisition on a silicon-based intensified CCD (iCCD). In fast-kinetics mode we achieve a physical frame rate of 100kHz with microsecond-scale gate control, and we directly capture the full evolution of an air-breakdown electric arc, resolving its rapid ignition, expansion, and decay dynamics. Beyond demonstrating ultrafast passive imaging, we introduce a drift-aware calibration workflow based on Allan deviation analysis to quantitatively select the gate width and averaging strategy under realistic slow-drift and multiplicative noise. This combined capability -- ultrafast passive MIR imaging plus operationally meaningful calibration -- provides a practical route toward real-time thermal surveillance and early-warning systems for hazardous fast transients.

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Jin-Peng Li, Zhi-You Li, Zhao-Qi-Zhi Han, Xiao-Hua Wang, He Zhang, Yin-Hai Li, Bo-Wen Liu, Wen-Tao Luo, Zhi-Yuan Zhou, Bao-Sen Shi. 2026-02-04. Passive Incoherent Ultrafast Mid-Infrared Upconversion Imaging and Its Calibration. https://arxiv.org/abs/2602.04483

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