Specifications:
| Materials | CVD ZnSe crystals | Size Tolerance | +0.0/-0.1mm |
| Central Thickness Tolerance | +/-0.1mm | Surface Quality | 40/20 S/D |
| Fringes (N) | <3 | Irregularity(delta N) | <1 |
| Centration | <3’ | Tolerance of Focal Length | +/-1% |
| Aperture | >90% | Chamfer | 0.1-0.3mmx45degree |
| Coating | AR/AR@10.6μm (T>99.5%@10.6μm) | ||
Basic Properties:
| Transmission Range | 0.6 to 21.0μm | Refractive Index | 2.4028 at 10.6μm |
| Reflection Loss | 29.1% at 10.6μm (2 surfaces) | Absorption Coefficient | 0.0005 cm-1 at 10.6μm |
| Reststrahlen Peak | 45.7μm | dn/dT | +61 x 10-6 /°C at 10.6μm at 298K |
| dn/dμ = 0 | 5.5μm | Density | 5.27 g/cc |
| Melting Point | 1525°C (see notes below) | Thermal Conductivity | 18 W m-1 K-1 at 298K |
| Thermal Expansion | 7.1 x 10-6 /°C at 273K | Hardness | Knoop 120 with 50g indenter |
| Specific Heat Capacity | 339 J Kg-1 K-1 | Dielectric Constant | n/a |
| Youngs Modulus (E) | 67.2 GPa | Shear Modulus (G) | n/a |
| Bulk Modulus (K) | 40 GPa | Elastic Coefficients | Not Available |
| Apparent Elastic Limit | 55.1 MPa (8000 psi) | Apparent Elastic Limit | 55.1 MPa (8000 psi) |
| Poisson Ratio | 0.28 | Solubility | 0.001g/100g water |
| Molecular Weight | 144.33 | Class/Structure | HIP polycrystalline cubic, ZnS, F43m |
Focusing Lens is an indispensable part of CO2 lasers designed for laser processing (cutting, punching, welding, graving, etc) and other kinds of purposes, serving to focus, collect, or collimate laser light. Shalom EO offers two shapes of laser focusing lenses, plano-convex and meniscus lenses. In general, Plano-convex ZnSe Lenses are the more conventional option, but for scenarios involving greater beam diameters and power densities, Meniscus ZnSe Lenses excel in terms of lower spherical aberrations. Zinc Selenide (ZnSe) is a popular material for the manufacturing of focusing lenses for CO2 lasers. ZnSe is favorable for CO2 laser and other IR applications with a wide transmission range of 600-16000nm and due to the fact that it has the lowest absorption compared to other common 1060nm CO2 laser wavelength transmitting materials, it exhibits prevailing advantages in circumstances in applications of high-power intensities. However, being soft, ZnSe might be more sensitive to scratches. For applications in dirty or high-splatter environments, Shalom recommends Our GaAs focusing lenses for CO2 lasers, which have a comparatively higher hardness and greater thermal endurance.
Hangzhou Shalom EO offers Plano-convex and Meniscus Zinc Selenide (ZnSe) Focusing Lens for CO2 lasers and versatile applications. For off-the-shelf versions, the specifications are Diameters 12.0-38.1mm, Central Thicknesses 2.6-7.87mm, Focal Length 38.1-190.5mm with 10.6μm AR Coatings. For custom versions, the maximum diameter is 200mm, suggesting that greater potential to handle higher power levels is available.
Shalom EO chooses CVD (Chemically Vapor Deposited) ZnSe grown in the USA which features exceedingly low bulk losses induced by absorption and scatter, high resistance to thermal shock, and stable properties that could cater to various operations environments. Due to the high refractive index of ZnSe, AR coating is critical to obtaining high transmission. In addition, Shalom EO incorporates the minimum-damage polishing technique during the coating process, and our AR coating ensures a high damage threshold, high durability, and wiping resistance, with an excellent transmittance of T≥99.5%@10.6mm. We also offer design services for the lenses, Shalom EO’s proficient and capable engineering team is prepared and willing all the time to deliver you the optimized mirror design and the best price effectiveness.
Application Notes:
While selecting the right focusing lens for your laser processing modules, you need to take several important considerations:
