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Silicon Windows （Si）
Silicon windows are infrared optical materials with a transmittance of 1.2um-8um. Coligh produces and customizes silicon optical windows of any shape <1000mm.
- Broad spectral transmittance: 1.2-8 µm
- Low density：ideal for lightweight applications
- High thermal conductivity：suitable for high-power laser systems
- High hardness and mechanical strength
- Customizable in any size and shape up to <1000 mm
- Coating services available
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Silicon Optical Large Size Windows Description
The silicon optical windows produced by Coligh cover the 1.2-8um band from near-infrared NIR to mid-infrared MIR, and are suitable for a variety of infrared optical systems.
- The transmittance in the 3-5um band is >50%, which is an ideal material for thermal imaging and infrared detection.
- The density of silicon is lower than that of germanium (Ge) and zinc sulfide (ZnS), which reduces the weight of the optical system and is suitable for weight-sensitive aerospace and portable devices.
- Its thermal conductivity is as high as 150 W/(m·K), which can quickly dissipate heat, reduce thermal lens effects, and withstand kilowatt-level laser power.
- In addition, its Mohs hardness is 7, and its scratch resistance is excellent, making it suitable for use in harsh environments.
Coligh can support large-size windows <1000mm
- It can be processed into flat, spherical, aspherical or any special-shaped structures.
- We can also provide customized coating services, such as broadband anti-reflection coatings, DLC protective films, spectroscopic coatings, and bandpass coatings
Silicon Optical Large Size Windows Detail Display
Silicon Windows Technical Datasheet
| Silicon Window Custom Option | |
| Windows Diameter Range | 3mm – 1000mm |
| RMS | 13/60nm full aperture |
| Shape | Customizable, any shape |
| Effective Aperture | >90% |
| Dimensional Tolerance | +0.0 / -0.02mm |
| Thickness Tolerance | ±0.02mm |
| Parallelism | 0.25″ |
| Chamfer | 0.2*45°mm |
| Surface Quality | 10/20 |
| Thin Film Coating | Broadband AR coating, reflective coating, metal coating |
Silicon Windows Applications
Silicon windows are widely used, mainly in the following core applications:
- silicon has a transmittance of 50%-90% in the 1.2-7um band, it is one of the few materials that can transmit far infrared. Therefore, silicon windows are often used in military thermal imaging analysis such as infrared cameras, CO₂ infrared spectrometer windows or special coatings to enhance hardness and corrosion resistance
- Silicon windows can withstand laser pulses >10 J/cm² (1064 nm wavelength) and can be used in high-power laser scenes to prevent cracking caused by local overheating
- In semiconductor manufacturing, silicon is used in extreme ultraviolet (EUV) lithography machines (13.5 nm wavelength) or wafer processing
- In the field of autonomous driving and lidar, silicon windows can adapt to the temperature range of -40℃-200℃ and can remain stable within a huge temperature change
- In medical and biological monitoring, silicon windows can be used for tumor screening such as skin cancer, and can also detect the crystal structure of drugs
