Open AccessConcurrent spatial and spectral filtering by resonant nanogratings
Author(s) -
Manoj Niraula,
Jae Woong Yoon,
Robert Magnusson
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.023428
Subject(s) - optics , polarizer , holography , broadband , spatial filter , interferometry , reflection (computer programming) , optical filter , focus (optics) , filter (signal processing) , spectral imaging , spatial frequency , physics , computer science , birefringence , computer vision , programming language
Optical devices incorporating resonant periodic layers constitute an emerging technological area. Recent advances include spectral filters, broadband mirrors, and polarizers. Here, we demonstrate concurrent spatial and spectral filtering as a new outstanding attribute of this device class. This functionality is enabled by a unique, near-complete, reflection state that is discrete in both angular and spectral domains and realized with carefully-crafted nanogratings operating in the non-subwavelength regime. We study the pathway and inter-modal interference effects inducing this intriguing reflection state. In a proof-of-concept experiment, we obtain angular and spectral bandwidths of ~4 mrad and ~1 nm, respectively. This filter concept can be used for focus-free spectral and spatial filtering in compact holographic and interferometric optical instruments.