Red-Selective Polymer Designed by Time-Dependent Density Functional Theory Calculation for Full-Color Image Sensing

Abstract

Strong color selective narrowband absorption is a major requirement for RGB-color- sensing photodiode components. The bioelectronic applications such as retina- prosthetic artificial vision would require flexible, biocompatible, and solution-treated polymer thin film for the strong color selective absorption. However, tuning a polymer for red color selective absorption is challenging, because the red color absorption in the region of 625-800 nm is often accompanied by green/blue color absorption in the region of 400-625 nm or by near-IR absorption in the region over 800 nm. In our study, for the strong red-selective absorption, we propose a narrow-wide-copolymer design rule which includes the following requirements: (1) HOMO and LUMO bands are localized in the narrow units; (2) HOMO-1 and LUMO+1 bands are localized in the wide units; (3) Hybridization between two units could be minimized by enforcing twist on backbone.