NIR‐II Temporal Compressive Wide‐Field Microscope (TCWM) Achieving Fluorescent Dynamic Imaging Beyond Camera Frame Rate

ABSTRACT Temporal compressive imaging enables the reconstruction of multi‐frame dynamic scenes from a single exposure by multiplexing spatially encoded temporal slices. This approach mitigates integration time loss and facilitates high‐speed imaging via low‐frame‐rate cameras. Herein, a second near‐infrared (NIR‐II) temporal compressive wide‐field microscope (TCWM) is established, utilizing the EfficientSCI algorithm for frame reconstruction. Simulations initially verify the transferability of EfficientSCI to biological microscopic imaging. Furthermore, mask acquisition with a spectrally matched NIR backlight proves effective for the high‐fidelity reconstruction of fluorescent targets. Utilizing a conventional NIR camera of 25 frames per second (FPS), NIR‐II TCWM achieves a maximum in vitro reconstruction rate of 333.3 FPS, surpassing the native frame rate by over 13‐fold. Additionally, its robust anti‐scattering capability for dynamic imaging at significant depths is substantiated using Intralipid. Finally, NIR‐II TCWM is applied to in vivo cerebrovascular imaging at depths up to 300 µm. With a 100 FPS reconstruction frame rate, NIR‐II TCWM successfully demonstrates simultaneous, high‐speed tracking of multiple fluorescent particles across multiple vessels, highlighting the potential for comprehensive deep‐tissue hemodynamic research in living organisms.