English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We design and characterize a novel axilens-based diffractive optics platformthat flexibly combines efficient point focusing and grating selectivity and iscompatible with scalable top-down fabrication based on a 4-level phase maskconfiguration. This is achieved using phase-modulated compact axilens devicesthat simultaneously focus incident radiation of selected wavelengths atpredefined locations with larger focal depths compared to traditional Fresnellenses. In addition, the proposed devices are polarization insensitive andmaintain a large focusing efficiency over a broad spectral band. Specifically,here we discuss and characterize modulated axilens configurations designed forlong-wavelength infrared (LWIR) in the $6~\mu$m--12~$\mu$m wavelength range andin the $4~\mu$m--6~$\mu$m mid-wavelength infrared (MWIR) range. These devicesare ideally suited for monolithic integration atop the substrate layers ofinfrared focal plane arrays (IR-FPAs) and for use as compactmicrospectrometers. We systematically study their focusing efficiency, spectralresponse, and cross talk ratio, and we demonstrate linear control ofmulti-wavelength focusing on a single plane. Our design method leveragesRayleigh-Sommerfeld (RS) diffraction theory and is validated numerically usingthe Finite Element Method (FEM). Finally, we demonstrate the application ofspatially modulated axilenses to the realization of compact, single-lensspectrometer. By optimizing our devices, we achieve a minimum distinguishablewavelength interval of $\Delta\lambda=240nm$ at $\lambda_0=8{\mu}m$ and$\Delta\lambda=165nm$ at $\lambda_0=5{\mu}m$. The proposed devices addfundamental spectroscopic capabilities to compact imaging devices for a numberof applications ranging from spectral sorting to LWIR and MWIR phase contrastimaging and detection.

Design of infrared microspectrometers based on phase-modulated axilenses