Laser induced optronic countermeasure against charge coupled devices and optronic counter-countermeasure in the visible region and infra-red region

摘要

A measurement of the photoelectric parameter (contrast, pixels affected) degradation of visible Focal-Plane Arrays (FPAs) irradiated by a laser has been performed. The irradiation fluence levels applied range typically from 300 μJ/cm~2 to 700 mJ/cm~2. A silicon FPA has been used for the visible domain. The effects of a laser irradiation in the Field Of View (FOV) and out of the FOV of the camera have been studied. It has been shown that the camera contrast decrease can reach 50% during the laser irradiation performed out of the FOV. Moreover, the effects of the Automatic Gain Control (AGC) and of the integration time on the blooming processes have been investigated. Thus, no AGC influence on the number of affected pixels has been measured, and it has been revealed that the integration time is the most sensitive parameter in the blooming action. Finally, only little laser energy is necessary for the system dazzling (1 μJ for 152 ns). A simulation of the irradiated images has been developed using a finite-difference solution. A good agreement has been shown between the experimental and simulated images. This procedure can be extended to test the blooming effects of IR cameras.