Wavelength-independent optical fully differential operation based on the spin–orbit interaction of light

Optical technology may provide important architectures for future computing, such as analog optical computing and image processing. Compared with traditional electric operation, optical operation has shown some unique advantages including faster operating speeds and lower power consumption. Here, we propose an optical full differentiator based on the spin–orbit interaction of light at a simple optical interface. The optical differential operation is independent of the wavelength due to the purely geometric nature of the phenomenon. As an important application of the fully differential operation, the wavelength-independent image processing of edge detection is demonstrated. By adjusting the polarization of the incident beam, the one-dimension edge imaging at any desirable direction can be obtained. The wavelength-independent image processing of edge detection provides possible applications in autonomous driving, target recognition, microscopic imaging, and augmented reality.