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2430/70nm Mid Infrared Bandpass Filter
2430/70nm Mid Infrared Bandpass Filter is designed to transmit around 2430nm and bandwidth 70nm. Coligh manufactures 2.0μm-30μm infrared bandpass filter
- Center wavelength 2430nm
- Bandwidth 70nm
- OD3 Blocking depth
- Transmission above 90%
- Single Substrate bandpass interference filter
- Custom center wavelengths from 2.0μm to 30μm
- Narrow band or wide band filter availiable
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2430/70nm Optical Mid Infrared Bandpass Filter Description
2430/70nm mid-infrared bandpass filter is a high-performance optical filter designed for the mid-infrared band (2395nm~2465nm).
- The central wavelength is 2430+/-20nm, with high transmittance within 2430+/-35nm, covering 2395nm~2465nm, and perfectly matches the characteristic absorption peaks of industrial harmful gases such as nitric oxide (NO) and hydrogen sulfide (H₂S), while being compatible with the wide-spectrum detection requirements of some hydrocarbon propane C₃H₈.
- The transmittance within the passband is greater than or equal to 90%, ensuring efficient capture of weak signals.
- The cutoff depth outside the passband is OD3 within the range of 200-3000nm, effectively shielding sunlight, thermal radiation and laser stray light interference.
- We specialize in the production of infrared filters. Both narrowband and broadband filters can be customized within the wavelength range of 2.0-30μm, and there is a large amount of inventory for customers to test.
2430/70nm Mid Infrared Bandpass Filter Technical Datasheet
| Parameter | Specification |
| Center Wavelength (CWL) | 2430 nm ± 10 nm |
| Transmission bandwidth | 2430+/-35nm |
| Peak Transmission | >=90% |
| Blocking Range | 200-3000nm |
| Optical Density (Blocking) | OD3 |
| Substrate Material | White Glass，Sapphire，Silicon ， Fused Silica , Zinc Selenide or other IR-grade substrate |
| Surface Quality | 80-50, 60-40, 40-20 scratch-dig (per MIL-PRF-13830B) |
| Clear Aperture | ≥ 90% of diameter |
| Typical Thickness | 0.5+/-0.1mm, 1.0+/-0.1mm |
| Typical Size | Dia25mm, Dia25.4mm, Dia50mm, Dia100mmm |
| Coating Type | Hard-coated dielectric |
| Environmental Durability | MIL-STD-810 compliant |
2430/70nm Mid Infrared Bandpass Filter Applications
- Industrial gas analysis
In the petrochemical refining process, hydrogen sulfide (H₂S) has a strong absorption peak near 2430nm. The 70nm bandwidth of the 2430/70nm filter can cover its main absorption line and adjacent harmonics, while eliminating water vapor interference. At the same time, in the high-temperature and high-humidity catalytic cracking unit, the H₂S concentration signal is accurately extracted, the background thermal noise is suppressed, and real-time online gas analysis is realized - Forest fire warning
In forest fires, the nitrogen oxides (NO) produced in the early stage of combustion release characteristic radiation in the 2430nm band. The 70nm bandwidth of the 2430/70nm infrared filter can capture the fire source signal and filter out the interference of sunlight reflection. In addition, with the infrared camera on the drone, it can generate a superimposed image of the heat source of the fire point and the gas distribution, which improves the accuracy of fire identification. - Medical breath diagnosis
The propane concentration in human breath can reflect the state of intestinal flora. The 2430nm band is sensitive to its C-H bond vibration. The bandwidth of this filter is suitable for the wide-spectrum detection of respiratory gas. In addition, the target gas signal is isolated in the breath analyzer, and background interference such as CO₂ and water vapor is shielded to achieve non-invasive intestinal disease screening.
