|Materials||CVD ZnSe crystals||Size Tolerance||+0.0/-0.1mm|
|Central Thickness Tolerance||+/-0.1mm||Surface Quality||40/20 S/D|
|Frings (N)||<3||Irregularity(delta N)||<1|
|Centration||<3’||Tolerance of Focal Length||+/-1%|
|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|
The Focusing Lens is an indispensable part of CO2 laser systems for laser processing (cutting, punching, welding, graving, etc) and other kinds of applications. There are conventionally two types of laser focusing lenses, plano-convex and meniscus lenses, which are both available in Shalom EO. Generally, Plano-convex ZnSe Lenses are the more conventional option, but for applications involving greater beam sizes and power densities, Meniscus ZnSe Lenses are more ideal in terms of lower spherical aberrations. Zinc Selenide (ZnSe) is a popular material to be manufactured into focusing lenses for CO2 lasers. ZnSe is advantageous due to having the lowest absorption compared to other common CO2 laser transmitting materials, therefore particularly suitable for high-power applications. However, being relatively soft, ZnSe might be more sensitive to scratches, for applications in dirty or high-splatter environments, Shalom offers GaAs focusing lenses for CO2 lasers, GaAs has a relatively high hardness and a greater thermal conductivity which helps to repel debris particles and transmit heat away from embedded particles.
Hangzhou Shalom EO offers Plano-convex and Meniscus Zinc Selenide (ZnSe) Focusing Lens for CO2 laser systems 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 the potentiality to handling higher power levels.
Shalom EO chooses CVD (chemically vapor deposited) ZnSe which features extremely low bulk losses due to absorption and scatter, high resistance to thermal shock, and stability in virtually all environments. Due to the relatively high refractive index of ZnSe， AR coating is critical to obtaining high transmission. Additionally, Shalom EO incorporates the minimum-damage polishing technology during the coating process, and our AR coating ensures a high damaging threshold, high durability, and wiping resistance, with an excellent transmittance of T≥email@example.com. Our experienced tech support is capable and willing to provide consultancy to deliver you the appropriate lens modules, which guarantee optimized interest for your laser systems, and economized costs. If you have any other specific requirements, we are also able to offer design services for custom focusing lenses.
While selecting the right focusing lens for your laser systems, you need to take several important considerations: