Nonmechanical zoom lens based on the Pancharatnam phase effect.

We present a nonmechanical zoom lens system based on the Pancharatnam phase effect, which is controlled by the state of circularly polarized light. The device is shown to allow for a compact design for a wide range of zoom ratios. A demonstration system is shown, which has a 4× zoom ratio between its two electrically switchable states. We show its observed image quality experimentally and compare it with calculated expectations.

Thin-film Pancharatnam lens with low f-number and high quality.

We have made an ultra-thin (~2.26 µm) f/2.1 lens based on the Pancharatnam phase effect using the polarization holography alignment technique. This lens exhibits a continuous phase profile, high efficiency (>97%), and is switchable from having a positive focal length to a negative one by changing the handedness of input circularly polarized light. We analyzed its optical performance and simulated it as a gradient index lens for further comparison, and to discuss its bandwidth limitation. The conditions required for improving the performance and its low-cost fabrication method is discussed. Because of the nature of Pancharatnam devices and the demonstrated fabrication method, these results are applicable to a wide size range.

Concept for a transmissive, large angle, light steering device with high efficiency.

A device concept is presented to allow very large angle deflection of light passing through a transmissive device. Deflection of light, switchable between angles larger than ±60 deg, is shown to be possible with efficiencies approaching 100%.