101.6mm (4") ZnSe CO2 Laser Focus Lens – 20mm Diameter

This 101.6mm (4-inch) CO2 laser focus lens is designed for cutting applications where greater depth of focus and additional working clearance are beneficial. Made from zinc selenide (ZnSe), the lens focuses the laser beam in compatible CO2 laser engraving and cutting machines operating at a 10.6µm wavelength.

The longer 4-inch focal length is particularly useful when cutting thicker materials or working with surfaces that have variations in height. Compared with shorter focal length lenses, it provides a greater depth of focus but generally produces a larger focused spot, making it less suitable for extremely fine engraving details.

Key Features

• 4-Inch Focal Length: Provides greater depth of focus for cutting thicker materials and applications with varying surface heights.
• Extended Working Distance: Allows additional clearance between the focusing lens and the workpiece when installed in a compatible optical assembly.
• Zinc Selenide Construction: Optical material commonly used to transmit and focus CO2 laser radiation.
• 20mm Diameter: Fits compatible focal tube assemblies designed for 20mm lenses.
• Plano-Convex Design: Focuses the incoming laser beam onto the workpiece.
• Thick Material Applications: A practical option for applications where depth of focus is more important than extremely fine engraving detail.

Technical Specifications

Compatibility

This lens is intended for compatible CO2 laser engraving and cutting machines that accommodate a 20mm diameter focusing lens and support a 101.6mm focal length.

Before ordering, verify your existing lens diameter, focal length, focal tube dimensions, and available focusing adjustment. A longer focal length may require a different focal tube or nozzle configuration to achieve proper focus and air assist positioning.

Cutting performance depends on laser power, material type, thickness, and machine configuration. A longer focal length does not automatically increase cutting capacity.

Handling & Maintenance

Handle the lens by its edges using appropriate protective gloves. Avoid touching either optical surface, and inspect regularly for residue, scratches, or damage. Clean only with products and procedures approved for ZnSe laser optics.

Always power down the laser machine and follow proper safety procedures before servicing optical components. Do not use damaged or cracked lenses.