Simultaneous chiral polarization and edge enhancement imaging enabled by a single geometric-phase-based element.

In this Letter, we propose a multifunctional imaging system enabled by a single geometric-phase-based liquid crystal (LC) element, which integrates chiral polarization and edge enhancement imaging. The element is located at the frequency domain plane in a 4F imaging system, and the phase profile of the element consists of a fork grating in the x direction and a grating in the y direction, which provide edge enhancement and chiral polarization imaging capabilities. Benefiting from the tunable property of the LC, the system can be switched from a polarization and edge imaging mode to the normal conventional imaging mode which is capable of conveniently acquiring the needed image information. Experiments demonstrate that the system can easily achieve multifunctional and switchable imaging, which agrees well with our design, and our LC element can work in the broadband spectrum because of the geometric phase modulation. The multifunctional strategy used here can effectively avoid the need to increase the size of the original microscopic system and the need for additional mechanical rotation of components. We believe that the proposed system with the additional advantages of electric control and tunability can find applications in biological imaging, medical detection, and optical computing.