Iridian launches high-uniformity bandpass filters

Iridian Spectral Technologies has authored a white paper on the uniformity challenge of large-format NBPFs.

Iridian Spectral Technologies (Ottawa, ON, Canada) has authored a white paper entitled "Large format NBPF--a uniformity challenge" describing its demonstration and manufacture of its extremely uniform large format (130 mm) narrow bandpass filter (NBPF).


An excerpt of the white paper follows:

Large format (>100 mm diameter), narrow bandpass filters (NBPF) are required in many fields. Applications requiring a large collection aperture drive the need for large collection optics, however high wavelength selectivity provided by narrow, flat-top bandpass optical filtering ( is also required to facilitate specific and selective analysis of a phenomena or substance of interest. The diversity of applications of these optics include earth observation remote sensing (whether satellite imaging or UAV mounted LIDAR), astronomical/solar imaging, UV micro-lithography tools, and live animal biological (fluorescence) imaging …

Iridian has addressed each of these challenges and has recently demonstrated the successful design and manufacture of an environmentally stable 1.72 nm-wide (FWHM) NBPF centered near 780 nm to within 20 pm of the wavelength target over an operating clear aperture >125 mm in diameter.

To view the white paper, go to:

SOURCE: Iridian Spectral Technologies;

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