Elimination of the interference of bias light for laser warning systems

In order to effectively restrain the interference of bias light from the surrounding environment for the spectral nonimaging pulse laser alarm device,after eliminating the bias light noise through light filtering,circuit filtering,comparator's threshold restrictions,aiming at the existence of huge energy background flash interference,according to the difference of the time length between background flash and pulse laser,calculating the incident light time of the alarm device based on complex programmable logic device and doing a judgment,the background flash interference can be eliminated.During the actual test,the false-alarm number of the alarm device caused by sunlight was 0 in 12h,and no false alarm happened in various simulating close and huge energy background flash interference situation.The result shows that the project can provides a good example and experimental scheme for resolving the false alarm problem cause by bias light of a laser warning device,the circuit hardware is highly integrated for judging time with only one complex programmable logic device chip,its program is short,and the method has good application value.