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11400nm (10.14um) Infared Dielectric Longpass Filter
11400nm infared dielectric longpass filter is designed to transmit longer wavelength than 11400nm and block shorter. Coligh manufactures infared longpass filter.
- 50% Transmission Wavelength at 11400 nm
- >75% High Transmission
- Broadband Blocking and Transmission
- Hard First-Surface Dielectric Coating
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Long‑wave Infrared Dielectric Longpass Filter With 11400nm Cut‑on Wavelength Description
11400nm (11.4μm) infrared dielectric long pass filter manufactured by Coligh is a hard dielectric thin-film coatings optical filter designed for far infrared with a transmission wavelength ≥10.14μm
- It has a wide spectrum transmittance, with a transmittance greater than or equal to 75% in the range of 11600-12250nm, which is suitable for signal acquisition needs such as ultra-far infrared thermal radiation and molecular rotation spectroscopy.
- The 50% transmission wavelength is strictly controlled within the range of 10.14μm+/-0.1μm, the cut-off depth OD>2 in the range of 7000-11000nm, and the transmittance is less than 1%, effectively eliminating mid-infrared noise
- We use hard dielectric film, which has strong adhesion and scratch resistance.
11400nm (10.14um) Infared Dielectric Longpass Filter Technical Datasheet
| Parameter | Specification |
| Cut‑on Wavelength (50% T) | 11400+/-100nm |
| High‑Transmission Band | ≥ 90% @ 11600nm-12250nm |
| Blocking Region | 7000nm-11000nm |
| Optical Density (OD) | OD >2 (T < 1%) |
| Substrate Materials | White glass, Sapphire, Silicon, Fused Silica, Zinc Selenide |
| Coating Type | Hard first‑surface all‑dielectric |
| Surface Quality | 80-50, 60‑40, 40-20 scratch‑dig (MIL‑PRF‑13830B) |
| Clear Aperture | ≥ 90% of full aperture |
| Available Diameters | Ø12.7 mm, Ø25.4 mm, or custom |
| Thickness | 0.5mm or custom |
11400nm (10.14um) Infared Dielectric Longpass Filter Applications
- Industrial high-temperature process monitoring
Nuclear reactor core and plasma flame temperature monitoring requires capturing ultra-far infrared radiation >10μm, but short-wave radiation such as visible light and X-rays can damage the detector and interfere with the signal.
The 11400nm long-pass filter can filter out short-wave noise and high-energy radiation <10.14μm, transmit 10.14-12.25μm thermal signals, and provide real-time feedback on temperature distribution. - Trace gas detection
The absorption spectrum of Freon is 11-12μm, and the absorption spectrum of hydrogen sulfide is 10.5μm. Freon and hydrogen sulfide are key indicators for environmental monitoring, but their absorption peaks are easily interfered by water vapor and CO₂. This filter can cut off short-wave noise <10.14μm and transmit the absorption peak of the target gas 10.14-15μm. Achieve wide-band transmission to support multi-component gas joint measurement - Quantum cascade laser
When quantum cascade laser works in 3-12um mid-infrared and far-infrared, it is necessary to isolate the fundamental frequency light and high-frequency harmonics to avoid signal crosstalk and detector damage. The 11400nm infrared filter can cut off the fundamental frequency laser <10.14μm and transmit the high-frequency signal >10.14μm, realizing the coordinated operation of multi-wavelength laser systems.
