Alfa Chemistry uses zinc selenide (ZnSe) to customize infrared optics devices. This is a polycrystalline material with many impressive properties, including high purity, high refractive index uniformity, chemical inertness, high damage threshold, insolubility in water, high resistance to thermal shock, non-hygroscopicity, and low volume loss. All of our custom ZnSe optics are rigorously tested by skilled experts at cutting-edge metrology facilities, giving our customers the peace of mind that their needs will be met. Contact us as soon as possible for customer service!
Our Services
Alfa Chemistry offers customization services for high-quality zinc selenide components including windows, lenses, and prisms that can be manufactured to your custom specifications. Our optical customization options include uncoated and coated. A common optical coating is a broadband anti-reflective coating. Our typical manufacturing specifications are listed below. If your requirements are not mentioned below, please contact our technical sales team and they will guide you through your inquiry.
ZnSe Windows
| Diameter Range | 5 mm ~ 100 mm |
| Diameter Tolerance | ± 0.1 mm |
| Centre Thickness | up to 50 mm |
| Centre Thickness Tolerance | ± 0.05 mm |
| Clear Aperture | 90% |
| Centration Tolerance | 1 arc minute |
| Form Error | better than λ/4 (633nm) over aperture |
| Surface Radius Tolerance | 1 fringe over aperture |
| Linear Dimension | up to 100 mm |
| Linear Tolerance | ± 0.1 mm |
| Angular Tolerance | 5 arc minutes |
| Edge Finish | ground, blacked |
| Chamfer | 0.3x0.3@45° |
| Surface Quality | 40-20 scratch/ dig |
ZnSe Prisms
| Length of Hypotenuse | up-to 50 ± 0.1 mm |
| Length of Sides | up-to 50 ± 0.1 mm |
| Thickness | 30 ± 0.05 mm |
| Angle Tolerance | better than 1 arc minute |
| Edge Finish | ground, blacked |
| Clear Aperture | 90% of entrance dimensions |
| Chamfer | 0.3x0.3@45° |
| Form Error | better than λ/4 @633 nm |
| Surface Quality | 20-10 scratch/dig |
ZnSe Ground Blanks
| Diameter Range | less than 5 mm to 100 mm |
| Diameter Tolerance | better than ± 0.5 mm |
| Centre Thickness | up to 50 mm |
| Centre Thickness Tolerance | better than ± 0.5 mm |
| Clear Aperture | 90% |
| Linear Dimension | up to 100 mm |
| Linear Tolerance | better than ± 0.5 mm |
| Angular Tolerance | better than 10 arc minutes |
| Edge Finish | fine ground N6 |
| Chamfer | 0.3x0.3@45° |
Applications:
- Carbon Dioxide Lasers: The fact that laser-grade ZnSe infrared lenses transmit at 10.6 µm with little absorption makes them popular choices for CO2 laser focusing.
- FLIR and Thermal Imaging: In applications involving thermal imaging and forward-looking infrared (FLIR), ZnSe optical windows are frequently utilized as protective windows. Typically, a broadband retroreflective coating is applied to these protective windows to minimize reflections into the system and increase transmittance.
- Fourier Transform Infrared (FTIR) Spectroscopy: Zinc selenide is the perfect substrate for attenuated total reflection crystals used in FTIR spectroscopy because of its broad transmission band.
ZnSe's Optical Properties
ZnSe is a medium refractive index material with good long-wavelength transmittance in the infrared. ZnSe material is suitable for use as mirrors and focusing lenses for high-power CO2 lasers because of its ultra-wide transmission range, high refractive index, and low infrared absorption. ZnSe easily transmits from 600 nm to 21 µm, with about 70% transmission between 1-15 µm.
In addition, ZnSe has excellent spectral range coverage and wear resistance, making it a popular material for attenuated total reflection studies. Because it is insoluble in water, it is a popular material of choice for radiographic examination of aqueous materials.
Below is a quick description of ZnSe's optical characteristics; click here to get the full data sheet.
| Transmission Range | 0.6 to 21 µm |
| Refractive Index | 2.4028@10.6 µm |
| Melting Point | 1525 ℃ |
| Density | 5.27 g/cm3 |
| Hardness | Knoop 120 with 50g indenter |
| Operating Temperature | < 250 ℃ in dry environment |
If you need technical advice, please contact our technical team to learn more about our high-quality services.