D27.9 ET4.1 Protective Window 1090nm 20 kW Germany Material for Fiber Laser Cutting Heads (10 pcs)

d27.9 × et4.1 mm protective window made from germany-sourced fused silica, ar-coated for 1090 nm and rated up to 20 kw. it shields the focus optics from spatter, fumes and dust in the cutting head.

size:

• diameter (d): 27.9 mm
• thickness (et): 4.1 mm
• pack: 10 × protective window

spec:

• ar coating optimised for 1090 nm fiber laser systems
• power rating: up to 20 kw in a clean, correctly aligned cutting head
• 4.1 mm thickness gives good stiffness and flatness under assist-gas pressure
• parallel, flat faces keep focal position and beam quality stable

material:

• quartz fused silica, germany-sourced material
• low absorption at fiber laser wavelengths, limiting thermal lensing
• durable ar coating on both faces

use:

• protective window in fiber laser cutting heads
• shields the focus lens from dust, fumes and metal spatter
• extends focus lens life and reduces unplanned cleaning stops

compatibility:

• for fiber laser cutting heads that use round d27.9 mm × et4.1 mm protective windows
• commonly used on raytools, wsx, bodor type heads and similar designs
• always confirm your original window diameter and thickness before ordering
• brand and model names are used for compatibility reference only; this is a plasarf replacement part, not an original oem part

quality:

• surface quality and coating checked before packing
• diameter and thickness verified against the marked size
• sealed packaging against dust and fingerprints