Abstract:The change laws of the characteristics of correlator have an important significance for the setting of its parameters in practical applications. Aiming at the joint Fresnel transform correlator (JFTC) with adjustable structure, the influence of the split width of Billet split lens (BSL) on the output and space-variant characteristics was analyzed in detail. The results show that the split width of the BSL can control the distribution size of the joint Fresnel power, the sharpness of the correlation peak, and the sensitivity of the space-variant characteristics. In the experiment, a structure-adjustable JFTC was constructed by using a phase-only spatial light modulator, which was encoded as a BSL phase mask to instead of a real lens. The experimental results are in good agreement with the simulation results, further verifying the correctness of the above conclusions.