Broadband infrared meanderline reflective quarter-wave plate

Abstract

We present a novel reflective quarter-wave plate comprised of subwavelength meanderline elements. The device is operational over the long-wave infrared (LWIR) spectrum, with significant spectral and angular bandwidths. Power reflection is approximately 70% over the majority of the LWIR. Efficient conversion from a 45° linear polarization state into circular polarization is demonstrated from finite-element electromagnetic simulations and from broadband polarimetric measurements.

Comparison of quarter-wave retarders over finite spectral and angular bandwidths for infrared polarimetric-imaging applications

“…1(b)) selected for this study represents a field of technology that has not yet been thoroughly investigated with regard to IR polarimetric-imaging. This device is the same 2-layer QWP component that was presented in [12], which is expected to exhibit achromatic polarimetric characteristics and angle-insensitive behavior, based upon past performance [12][13][14][15]. Multilayer meanderline QWPs have technological potential that could be employed in thermal IR po-larimeters, especially considering that they can be fabricated into a compact planar form factor that facilitates integration with other polarization devices and pixelated IR sensors.…”

“…A. Woollam Corp.) over the 8-12 μm band. These parameters include δ, the differential phase shift, and ψ, the auxiliary angle, which determine the axial ratio (AR), defined as the ratio between the major and minor axes of the transmitted polarization ellipse [2,12,13]…”

Tunable reflective liquid crystal terahertz waveplates

“…THz polarization conversion with commercial quartz waveplates is mechanically controlled [4]. Mechanically tunable THz reflective waveplates exhibit a dependence on incidence angle and separation distance [5]. However, mechanically tunable devices are bulky and difficult to integrate.…”

Directional thermal emission from a leaky-wave frequency-selective surface

“…5 This makes FSS a type of metamaterial (a metasurface) with electromagnetic properties typically not found in nature. FSS has been used to control the spectral, 6-8 phase, [9][10][11] and polarization 12 responses of incident radiation. This is often achieved via scaling established radio frequency designs to infrared wavelengths 13 which has significance at infrared wavelengths because it controls the emissivity of the surface, and hence heat transfer via radiation.…”