Polarization Specific Edge Enhancement Enabled by Compact Dielectric Metasurface Imaging System

All optical information processing and identification enables high speed, low power consumption, and efficient complex data processing. Optical edge enhancement can extract structural and morphological information about an object; however, existing systems require bulky and complex optical configurations. Development of a low-cost, lightweight, integrable, and high-performance imaging system is thus necessary for biomedical and industrial applications in the field and onsite. Here we propose and demonstrate a compact metasurface imaging system composed of cascaded metasurfaces that function as a metalens and q-plate for isotropic edge enhancement of amplitude objects, phase objects, and biological specimens. Furthermore, we utilize the polarization degree of freedom of light in addition to amplitude and phase to achieve anisotropic edge enhancement. By utilizing different polarization states of incident light, the impulse response of the metasurface imaging system is modified to achieve real-time isotropic and directional edge enhancement while maintaining a field of view. The proposed approach demonstrates a robust, ultracompact, lightweight, efficient, and integrable platform for reliable, stable, and cost-effective point of care devices, process control, and monitoring.