Long Pass Filters….
Long-pass filters transmit light above the cut-off wavelengths and attenuate the lower wavelengths.
They are often used extensively in spectroscopy, thermography, metrology and device engineering for the purpose of isolating a region, with the substance or substances to be detected, from other regions that may add noise or inaccuracy to the measurement.
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Narrow bandpass filters are optical components that select a narrow wavelength range of a much broader light spectrum. In mid-infrared region they are used in gas sensors, spectrometers or thermal cameras to detect gases.
Typical applications are gas leak detection and hazardous gas monitoring in industry, environmental monitoring, gas identification in aerospace or in medical applications, among others.
Mapsi Photonics manufactures all-silicon filters which, in addition to being suitable for conventional applications, are particularly interesting in harsh environments, such as those involving high temperatures and/or high pressures. For instance, measuring gases in industrial chimneys.