Wavelength-tunable deep-ultraviolet thin-film filter: design and experimental demonstration

Abstract

A deep-ultraviolet (DUV) narrowband tunable filter with a central wavelength of 225.0 nm is designed, fabricated, and demonstrated experimentally. The simulation results showed a transmittance of about 42.1% at 225.0 nm and a full width at half-maximum (FWHM) of ∼ 1.2 n m . The experimental results for normal incidence light revealed a corresponding central wavelength of 225.0 nm, a transmittance of 27.7%, and a FWHM of 1.9 nm. By changing the incident angle, the central wavelength can be tuned from 225.0 to 224.5 nm. This DUV narrowband tunable filter has been shown to demonstrate good performance and has broad applicability.

Femtosecond Laser Modification of Silica Optical Waveguides for Potential Bragg Gratings Sensing

“…TFFs have the advantages of a narrow passband, low loss, and good temperature stability. However, the fabrication process is a little complex and sometimes more than 100 layers may need to be coated [12,13]. The Bragg grating can reflect the designed wavelength and is considered a promising candidate for WDM systems.…”