Simulation of Mixture Frequency Laser Irradiation on CCD Detectors

CCD arrays can be disturbed or damaged when subjected to laser irradiation,in order to strengthen the damage effect,a kind of mixture frequency laser interference method is put forward,which can couple the high repition frequency laser with the low repition frequency laser to make the both laser irradiate on the CCD in the meantime.The thermal mechanical physical model of CCD light shading Al film irradiated by the mixture frequency laser is set up based on heat conduction and thermal elastic mechanics theories,the heat conduction differential equation and stress-balance equation are solved by the semi-analytical method and the instant temperature field and thermal stress field of light shading Al film are obtained.The damage effects of the CCD locater irradiated by the lasers at different working modes are compared by numerical simulations quantitatively.The results show that,compared with the CCD irradiated with only the high repition frequency laser or the low repition frequency laser,CCD arrays will be damaged much more heavily when subjected to the mixture frequency laser irradiation.