Laser-dazzling effects on TV cameras: analysis of dazzling effects and experimental parameters weight assessment

Imaging systems are widespread observation tools used to fulfil various functions such as detection, recognition, identification and video-tracking. These devices can be dazzled by using intensive light sources, e.g. lasers. In order to avoid such a disturbance, dazzling effects in TV-cameras must be better understood. In this paper we studied the influence of different parameters on laser-dazzling. The experiments were performed using a black and white TV-CCD-camera, dazzled by a nanosecond frequency doubled Nd:YAG laser. Different dazzling conditions were studied by varying for instance the laser repetition rate, the pulse energy or the settings of the camera. We proceeded in two steps. First the different dazzling effects were analyzed and classified by their mainspring. Pure optical phenomena like multiple reflections, scattering and diffraction were discriminated from electronics effects related to charge transfer processes. Interactions between the laser repetition rate and the camera frequency or the camera exposure time were also observed. In a second step, experiments were carried out for different dazzling conditions. It was then possible to assess the weight of each experimental parameter on dazzling effects. The analysis of these quantitative results contributes to the better understanding of laser-dazzling, useful to design efficient means to protect imaging systems.