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940nm Filter FWHM 40nm
940nm Filter FWHM 40nm is an optical bandpass filter optimize for 940nm wavelength. Coligh manufactures EUV to 30000nm bandpass filters for various applications.
- Center Wavelength 940nm
- FWHM 40nm
- Tp≥90%
- OD4 deep blocking depth
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940nm Optical Bandpass Filter FWHM 40nm Description
940nm Filter FWHM 40nm is designed to select transmit light centered around 940nm.
- The 940/40nm interference filter produced by our hard multilayer dielectric film technology has the following characteristics:
- Central wavelength 940+/-2nm, perfectly matching the near-infrared light source emission band
- Half bandwidth 40+/-4nm, covering the range of 900nm-980nm, compatible with light source wavelength drift.
- The peak transmittance is greater than or equal to 90%, ensuring efficient use of effective optical signals and reducing supplementary light power consumption.
- The cut-off depth OD4 in the range of 200-1700nm outside the passband significantly suppresses interference from sunlight and other ambient light.
940nm Optical Filter FWHM 40nm Technical Datasheet
| Parameter | Specification |
| Center Wavelength (CWL) | 940 nm ± 2 nm |
| FWHM | 40 nm ± 4nm |
| Peak Transmission | ≥ 90% |
| Blocking Range | 200 – 1700nm |
| Optical Density (OD) | OD4 |
| Angle of Incidence (AOI) | 0° |
| Clear Aperture | >90% of the diameter |
| Substrate Material | UV Fused Silica, K9,sapphire, Other optical glass |
| Size | Ø12.7mm, Ø25.4mm,Ø50.8mmor customizable |
| Environmental Durability | Compliant with MIL-STD-810G |
| Other avaliable wavelength | 940/10nm,940/20nm,940/30nm,940/50nm,940/60nm,940/70nm,940/80nm |
| Custom Option | EUV to 30,000nm |
| Filter Type | Multilayer Interference Bandpass Filter |
| Coating Technology | Ion-Assisted Deposition (IAD), Hard coated |
| Surface Quality | 80-50, 60-40, 40-20 (per MIL-PRF-13830B |
940nm Bandpass Filter FWHM 40nm
- Infrared lighting
High-power 940nm LEDs will produce wavelength drift when working for a long time, and the edge light will have an angle shift when illuminating at a wide angle. The 940/40nm bandpass filter has a bandwidth of 40nm, ensuring that effective infrared light can be efficiently transmitted even if the LED wavelength shifts or the optical system has an angle deviation. Avoid the problem of edge light intensity attenuation during wide-angle lighting - Industrial flame detection
Flames of different dyes have different infrared radiation characteristics. The infrared radiation peak of natural gas flames is 935nm, the secondary peak is 960nm, and the flame radiation peak of alcohol is 920-970nm. 940/40nm has two peaks for detection, 935nm and 960nm, which can cover the radiation peaks of multiple fuels, so that flames of different dyes can be accurately identified - Agricultural product moisture detection
Water has a wide absorption band near 940nm, but different crops have different absorption characteristics. For example, the absorption peak of tea is 935nm, and the absorption peak of rice is 945nm. The bandwidth of 940/40nm bandpass filter in 920-960nm can adapt to a variety of crops - Industrial welding
The temperature monitoring of the molten pool during welding requires 940nm characteristic radiation. The 940/40nm filter can be used for real-time temperature feedback, and the quality of the weld can be inverted through the 940nm radiation intensity.
