Circularly polarized optical microscope using a low aberration liquid crystal lens

We demonstrate a circularly polarized optical microscope (POM) by incorporating a hole-patterned electrode (HPE) liquid crystal (LC) lens fabricated by photoalignment. The focal plane is controlled by voltages on the HPE LC lens with a tuning range of 2.2 mm without any mechanical movement. The diopter can be controlled from 0 to -5.0 D, and the wavefront optical path difference is less than 0.25λ for our proposed HPE LC lens. Such a low aberration is obtained, because the LC directors are well aligned along with the axially symmetrical electrical field, and there is no observed twist deformation of the LC directors. Finally, we applied our circularly polarized POM to inspect the reflectance properties of several beetles, and we find that the "Chrysochroa toulgoeti"beetle exhibits right circularly polarized reflectance from some small areas on its wings.