Optical differential operation near exceptional points

As the core principle of optical image edge detection, optical differential operation shows some unique advantages compared to traditional digital image processing, including simple structure, higher efficiency, and lower power consumption. This paper proposes that spin-dependent splitting and parity-time (PT) symmetry in the photon spin Hall effect (SHE) can be used to achieve optical differential operation near exceptional points. Firstly, we theoretically prove that optical differential operations can be realized near exceptional points in parity-time (PT) symmetric systems. Then, we discuss the influence of different factors on beam displacement. Due to the beam displacement changes with these factors, it is found that one-dimensional edge imaging in any direction can be achieved by adjusting the incident angle, the incident polarization, and the imaginary part of the refractive index of the PT-symmetry system. This will provide the possibility to improve the speed of pattern recognition, the accuracy of intelligent driving, and the ability of microscopic imaging.