Damage analysis of CMOS electro-optical imaging system by a continuous wave laser

Abstract

EOIS (electro-optical imaging system) is vulnerable to laser beam because EOIS focuses the incident laser beam onto the image sensor via lens module. Accordingly, the laser-induced damage of EOIS is necessary to be identified for the counter-measure against the laser attack. In this study, the damage of CMOS EOIS and image sensor induced by CW (continuous wave) NIR (near infrared) laser was experimentally investigated. When the laser was emitted to CMOS EOIS, a temporary damage was occurred first such as flickering or dazzling and then a permanent damage was followed as the increase of laser irradiance and irradiation time. If the EIOS is composed of the optical equipment made of heatresistant material, laser beam can penetrate the lens module of EOIS without melting the lens and lens guide. Thus, it is necessary to investigate the damage of CMOS image sensor by the CW laser and we performed experimentally investigation of damage on the CMOS image sensor similar with case of CMOS EOIS. And we analyzed the experiment results by using OM (optical microscopy) and check the image quality through tomography. As the increase of laser irradiance and irradiation time, the permanent damage such as discoloration and breakdown were sequentially appeared.