Evolution of interference and damage in a front-illuminated CMOS photodetector under 1064  nm high-repetition-rate nanosecond pulsed laser irradiation.

High-repetition-rate nanosecond pulsed lasers produce irradiation effects on CMOS photodetectors through the coupling between single-pulse transient photoelectric responses and multi-pulse thermal accumulation. The evolution from interference to damage under varying power and repetition rate conditions remains insufficiently understood. This study irradiated front-illuminated CMOS photodetectors with a 1064 nm high-repetition-rate nanosecond pulsed laser at average powers of 1 and 10 W with repetition rates from 1 to 3 MHz. A deviant pixel ratio method based on differential images and the 3σ criterion was established to quantify interference evolution and post-irradiation recovery. At 1 W, the detector sequentially underwent an initial transient response, black sun effect, interference expansion, and global saturation, recovering to near-baseline status after laser cessation. The recovery time extended from 402±67 ms at 1 MHz to 1809±67 ms at 3 MHz. At 10 W, the detector underwent readout sampling anomaly, saturation crosstalk, and cross-shaped functional damage with irreversible structural damage. The deviant pixel ratio at all repetition rates failed to fall below the single-pixel resolution limit after laser cessation, confirming irreversible functional damage that intensified with repetition rate. These results provide a basis for evaluating interference and damage effects of high-repetition-rate nanosecond pulsed lasers on CMOS photodetectors.