High-Performance Diamond Optical Windows for Extreme Photonic Applications

High-Performance Diamond Optical Windows for Extreme Photonic Applications

In advanced optical systems—such as EUV lithography high-power laser windows, wafer laser annealing systems, and microwave windows in gyrotrons for controlled nuclear fusion—conventional optical materials are limited by narrow spectral transmission, poor environmental stability, and low damage thresholds.

SEMIXICON DIASEMI  has developed high-performance diamond optical materials featuring ultra-broad spectral transmission and exceptional multi-physics stability, providing comprehensive  technical solution for next-generation optical windows.

Ultra-Broad Spectral Transmission & Superior Optical Properties

Diamond’s unique crystal structure enables transmission across an exceptionally wide spectral range—from ultraviolet to microwave—while maintaining outstanding physical and chemical robustness:

• High Transmittance

• Single-crystal IR transmittance: >71%

• Polycrystalline IR transmittance: >70%

• Stable transmission across UV, IR, and microwave regimes

• Extreme Stability

• Chemically inert: resistant to acids and alkalis

• Ultra-high hardness (Mohs 10): superior wear and impact resistance

• High thermal shock and radiation resistance

• No performance degradation over long-term operation

Compared with conventional materials such as optical glass, sapphire, and ZnS, diamond offers significantly enhanced durability and broader operational bandwidth.

Precision Manufacturing: Large Size + High Accuracy

Enabled by in house developed advanced MPCVD processes, both single-crystal and polycrystalline diamond optical components are produced in bulk now with high consistency:

• Large-Area Capability

• Single crystal: up to 20 × 20 mm

• Polycrystalline: up to Ø100 mm

• Ultra-Precision Finishing

• Surface roughness: < 3 nm

• Parallelism: < 5 μm

• Figure accuracy: < 1 μm

• Custom Engineering
  Fully customizable in size, shape, and thickness for applications including Raman laser optics, gyrotron microwave windows, and high-power CO₂ laser systems.

Application Coverage: Enabling Next-Generation Technologies

Diamond optical windows are critical enablers across multiple frontier domains:

• High-Power Laser Systems
  High thermal conductivity minimizes thermal lensing and ensures beam quality and long-term stability

• Radiation & X-ray Systems
  High transmission and low absorption make diamond ideal for synchrotron, medical imaging, and NDT applications

• High-Power Microwave Devices
  Excellent thermal and dielectric properties support reliable transmission of megawatt-level microwave energy

• Extreme Environments