In the Bragg wavelength-regime, a sculptured thin film with chiral micromorphology permits light of a particular circular polarization state to pass virtually unhindered, but light of the other polarization state is reflected almost completely. This circular Bragg phenomenon is shown here to admit narrow-band spectral reflection holes analogous to those well-studied as phase defects within grating structures. Application to the design of an ultranarrow-bandpass circular-polarization filter is considered, with the location, bandwidth and polarization selectivity quantified via a particular set of numerical examples.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering