Broadband Polarization-Independent Directional Control of Visible and Infrared Light

Abstract

Broadband polarization-independent directional control of light has long been a grand challenge despite its immense potential in enhancing energy efficiency, improving performance of optoelectronic devices and enabling privacy protection display. Existing devices for controlling light direction suffer from inefficiency, bulkiness, and strict limitations in material composition. We develop a highly miniaturized micro compound parabolic concentrator (MCPCs) array, which overcomes these limitations and demonstrates broadband polarization-independent directional control across the visible, near-infrared, and mid-infrared spectra.

In addition, our research showcases the wide-ranging applications enabled by advanced directional control of light. Through the integration of MCPC arrays with thermal emitters, we have created a bright directional emitter that deviates from the intrinsic isotropy of blackbody emission, resulting in more efficient radiant thermal transfer. By integrating the MCPC arrays with thermal radiation detectors, we effectively filter out environmental noise, thereby enhancing the detector's signal-to-noise ratio. Furthermore, we demonstrate the ability to fabricate MCPC array over large scale, broadening its potential applications. Privacy-protecting display is achieved and radiative cooling decoupled with solar spectrum engineering is demonstrated