Low Absorption Protective Windows

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Low Absorption Protective Windows are widely used in laser processing to ensure high transmission of laser energy, protect the laser system, and minimise thermal effects.

OPTOMAN protective windows are IBS coated and optimized for high laser power and controlled Z-shift.

OPTOMAN capabilities

Coating technology – Ion Beam Sputtering (IBS)
Size for round windows: <420 mm, for square windows: 500 x 200 mm
Surface quality: up to 10-5 S-D (MIL-PRF-13830B)
Agility, flexibility, and quick prototyping
High repeatability

Application-optimized products for additive manufacturing, cutting, welding, and drilling

Laser additive manufacturing enables the precise creation of complex metal and polymer parts. 3D printing technologies like DMLS or SLM are widely applied in the aerospace, healthcare, and automotive industries. Additive manufacturing heavily relies on high-power and long-lifetime laser optics. Low absorption and controlled thermal lensing play an essential role here. Furthermore, cutting, welding, and drilling enable precise material processing in the automotive, aerospace, and electronics industries. However, challenges in laser optics, including thermal lensing, beam profile deformation, cleaning the optical element surface, and Laser-induced damage, require careful management to ensure efficiency.

IBS coating

Ra < 0.1 % @ 1060-1070nm + Ra < 2 % @ 633nm
AOI = 8 ± 8° cone
Absorption: <3 ppm
LIDT: >426* kW/cm @ 1070nm, 30s, 137.6 µm

*426 kW was the power limit of the laser

IBS coating Ra < 0.1 % @ 1060-1070nm + Ra < 2 % @ 633nm AOI = 8 ± 8° cone

Figure 1. Longitudinal scan.

Figure 2. Damage probability plot.