Abstract: In this paper,it is suggested that the optical window of the optical electrical apparatus is scanned with a laser beam to found the laser transformation characteristics of the window for recognition of the optical electrical apparatus.It is the fact that the each optical electrical apparatus has some inhe rent laser transformation features.Based on the fact,a data base of the transformation features of the optical electrical apparatus can be established.It will play a important role in these fields of the optical electrical countermeasure,laser active recognition and laser radar.