Abstract: To study the influence of background on detection, a 3-D noise model and a measurement system were established. The temporal noise and spatial noise of CCD camera were measured and analyzed at different illuminances. The block diagram of the test system and some test results are given. The dominant noise which influences the output quality of CCD image was found, the dependence of temporal noise and spatial noise on illuminance was obtained. Measurement results indicate that the spatial noise and temporal noise increase with the increase of illuminance on the active area of CCD camera. It is consistent with the performance of CCD cameras.