title: Thin-film Pancharatnam lens with low f-number and high quality.
abstract: 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.
authors.forename: Kun
authors.initials: K
authors.lastname: Gao
authors.forename: Hsien-Hui
authors.initials: HH
authors.lastname: Cheng
authors.forename: Achintya K
authors.initials: AK
authors.lastname: Bhowmik
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Bos