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3000-5000nm AR Coated Silicon IR Windows
3000-5000nm AR Coated Silicon IR Windows is infrared windows designed for mid-wave infrared applications. Coligh manufactures various IR windows up to 30000nm
- Wavelength range is 3000-5000nm high transmission and low reflection
- Broad band AR coating for 3000-5000nm
- Silicon substrate
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AR Coated Silicon Infrared Window for 3000-5000nm Wavelength Description
3000-5000nm AR Coated Silicon IR Windows Coligh manufactures uses high-purity single crystal silicon as the material and anti-reflection coating for optical windows in the wavelength range of 3000-5000nm.
- We use multi-layer AR coating technology to effectively suppress double-sided reflection, with a transmittance of greater than or equal to 95% in the range of 3-5μm and a reflectivity of less than 2%
- Single crystal silicon has a natural high transmittance in the 3-5μm band, but its surface will cause a reflection loss of about 30% due to a sudden change in the refractive index.
- As a substrate, silicon itself has stability in extreme environments. Resistant to high temperature and thermal shock, the operating temperature range is -100°C to +250°C, and the Mohs hardness is 7, and the anti-sand and scratch performance is better than germanium and zinc selenide
- We can provide customers with a variety of customization, including size, thickness, diameter, shape, extended band, etc.
3000-5000nm AR Coated Silicon IR Windows Technical Datasheet
| Parameter | Specification |
| Substrate Material | Silicon |
| Wavelength Range | 3000-5000nm |
| Coating Type | Anti-Reflective (AR) |
| Average Transmittance | ≥ 95% (within 3000-5000nm range) |
| Surface Quality | 60-40, 40-20 |
| Coating Method | Ion-assisted deposition / Electron-beam evaporation |
| Custom Options | Available upon request (wavelength tuning, dual-side，size up to 10000mm, any shape to be customized) |
3000-5000nm AR Coated Silicon IR Windows Applications
- Gas detection and analysis
Gas molecules have characteristic absorption peaks in the mid-infrared band of 3-5μm, such as [email protected]μm and CH₄@3.3μm. High transmittance windows are required to accurately capture weak absorption signals. Traditional uncoated silicon windows have high reflection losses, resulting in insufficient detection sensitivity. 3000-5000nm AR Coated Silicon IR Windows As the optical window or gas cell transmission element of the gas analyzer, AR coating can increase the transmittance to >95%, reduce the energy loss of the optical path, and enhance the signal-to-noise ratio. - Industrial laser processing
High-power mid-infrared lasers, such as 4.6μm quantum cascade lasers, require low-loss transmission windows. Reflection losses of uncoated silicon windows lead to energy waste, and traditional zinc selenide windows are easily oxidized by moisture. This infrared window can be used as a protective window for the laser output head. AR coating can reduce the reflectivity to <2%, improve laser energy utilization, and resist dust pollution in the processing workshop. - Military and security
In battlefield environments, infrared imaging systems need to maintain a clear field of view under dust, humidity and heat conditions. Traditional germanium windows are bulky and fragile, and zinc selenide windows are not hard enough. 3000-5000nm AR Coated Silicon IR Windows can be used as a protective window for infrared detectors, transmitting thermal radiation signals in the 3-5μm band while resisting dust friction and mechanical shock. In addition, the high transmittance ensures the accuracy of target recognition at night and in haze environments, and the anti-vibration design is suitable for vehicle-mounted and airborne equipment. - Medical diagnosis
Human tissue releases thermal radiation in the 3-5μm band, but weak signals are easily masked by optical component losses, and high transmittance windows are required to ensure diagnostic accuracy. In cancer thermal imaging and laser treatment, this infrared window can be used as a window for infrared thermal imagers or laser treatment equipment, efficiently transmitting thermal signals or laser energy to avoid energy loss leading to misdiagnosis or delayed treatment.
