Polarization-dependent characteristics of a photon-counting laser ranging system

We have built a photon-counting dual-polarization-sensitive time-division laser ranging system. The laser source can emit linearly polarized light with both horizontal and vertical polarizations, and the polarization-sensitive receiving module counts the echo photons in the two polarization states separately. By analyzing the scattering characteristics of target surfaces and counting the numbers of echo photons with different polarizations, metallic and nonmetallic surfaces can be distinguished. The proposed photon-counting system takes advantage of its high detection sensitivity and polarization-sensitive detection to obtain information on the target surface. Together, these two features improve the detection efficiency of the system as a whole and enable secure target detection.