In terms of the mechanism of common single-channel and multi-channel laser measurement methods and the existing difficult real time measurement problem, an idea to use a laser array to measure the jamming efficiency of smoke against infrared radiation is proposed. By using the homogenized shaping technology for infrared laser beams, the real time measurement of the infrared transmittance of infrared imaging is implemented when smoke jamming is used. The random problem in transmittance measurement caused by the changing of smoke in an infrared imaging field of view is solved. By calculating the measurement results of different methods under a typical test condition, the quantitative analysis is made for the improvement of measurement accuracy.