Testing device for modulation transfer function of push-broomelectro-optical imaging system

The optical remote sensing system obtains a high resolution imaging of ground targets by the imaging model of linear array CCD push-broom. And the modulation transfer function (MTF) is a key parameter to evaluate the imaging quality of push-broom system. Using the black and white stripe target as a square wave signal of Nyquist frequency to test the static MTF can evaluate the imaging quality of system quantitatively. However, an electrooptical imaging system with linear array CCD push-broom model has to test its dynamic MTF under the image motion compensation and drift angle control condition, and then the imaging quality of system in the real working condition can be evaluated. Based on the theory of dynamic and static MTF testing methods, we studied the constitution and the working principle of testing device, and gave a detail designing for collimator, static and dynamic target generator. The wavefront error of collimator was better than 25 nm (RMS). The focus length adjusting accuracy was better than 3 m. The output accuracy of image motion compensation was better than 5/1 000. And the illumination uniformity of system was better than 95%, which could realize a theoretic non-coherent illumination. The simulated designing above could satisfy the dynamic and static MTF testing requirement for the new optical remote sensing imaging system in laboratory.