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Characterization of Narrow-Band Infrared Interference Filters



Simon G. Kaplan, Leonard M. Hanssen


A Fourier-transform infrared (FT-IR) spectrophotometer system is used to measure the transmittance of infrared band-pass filters as a function of wavelength, temperature, and beam geometry. Measurements are performed using an f/4 beam geometry at normal incidence, or a nearly collimated geometry with variable angle of incidence. Blocking filters are used to expand the dynamic range of the out-of-band measurement to transmittances as low as 10-6 with 4 cm-1 resolution.
SPIE series


filter, infrared, transmittance


Kaplan, S. and Hanssen, L. (1998), Characterization of Narrow-Band Infrared Interference Filters, SPIE series (Accessed May 17, 2024)


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Created October 8, 1998, Updated June 27, 2017