Transmission and control of polarization modulation light filed in free space

As a new degree of freedom for light manipulation, the polarization state of a light field is gradually becoming a focused issue. The photon spin-orbit intercoupling can be achieved by the non-uniform modulation for the polarization state of the light filed, and then a variety of novel optical phenomena can be explored. Thereinto, the Pancharatnam-Berry (PB) phase plays an important role. In the polarization conversion, different polarization components of the light field are with different PB phases. We can control the transmission of the polarization components of the light field by using PB phases to shape the wave fronts of the polarization components, and achieve the polarization conversion, spin-orbit conversion, and energy flow management in the process of the light transmission. The related research of light polarization modulation has potential application values in spin-selected imaging, particle manipulation, laser micro-processing, and information transmission and recovery. We discuss the mechanism of transmission and manipulation of the polarization modulation light field, and present an overview of the recent research in this field.