In order to analyze the performance of the laser emission system, it was necessary to measure the spatial-temporal distribution of the absolute power density of the laser spot. The detector array target was one of the effective methods. To achieve quantitative analysis, the detector array target needed to be calibrated. The number of detector array target units was large, and the calibration was difficult. It was very important to design an effective calibration system. This paper designed a new calibration system, which adopted the point-by-point scanning method. This way had the characteristics of wide applicability, low cost and high precision. In order to test the system, taking a project as an example, the measurement uncertainty of the calibration system was tested and analyzed. The results show that the measurement uncertainty in the visible light band is 2.99%, and the measurement uncertainty in the near-infrared band is 3.62%. The measurement uncertainty in the mid-infrared band is 6.17%. This calibration system was an effective way for target calibration of detector array, it was worth learning.