Nonmetallic Broadband Visible-Light Absorbers With Polarization and Incident Angle Insensitivity

Wide-angle, polarization-independent ultrathin broadband visible absorbers

A broadband wide-incident-angle reflective polarization converter

Yan Li (SID Student Member) Thomas X. Wu (SID Member) Shin-Tson Wu (SID Fellow) Abstract — A high-performance reflective polarization converter which could be used in a backlight recycling system for liquid-crystal-display (LCD) devices is proposed. The device consists of a twistednematic (TN) liquid-crystal film, a uniaxial A-plate, and a reflector. The configuration parameters, such as thickn...

Effects of Incident Angle and Distance on Visible Light Communication

Visible Light Communication (VLC) provides wireless communication features in illumination systems. One of the key applications is to recognize the user location by indoor illuminators such as light emitting diodes. For localization of individual receivers in these systems, we usually assume that receivers and transmitters are placed in parallel. However, it is difficult to satisfy this assumpt...

New Insight into the Angle Insensitivity of Ultrathin Planar Optical Absorbers for Broadband Solar Energy Harvesting

Two challenging problems still remain for optical absorbers consisting of an ultrathin planar semiconductor film on top of an opaque metallic substrate. One is the angle-insensitive mechanism and the other is the system design needed for broadband solar energy harvesting. Here, first we theoretically demonstrates that the high refractive index, instead of the ultrathin feature as reported in pr...

All-Silicon Ultra-Broadband Infrared Light Absorbers

Absorbing infrared radiation efficiently is important for critical applications such as thermal imaging and infrared spectroscopy. Common infrared absorbing materials are not standard in Si VLSI technology. We demonstrate ultra-broadband mid-infrared absorbers based purely on silicon. Broadband absorption is achieved by the combined effects of free carrier absorption, and vibrational and plasmo...