Applications
Optics & Photonics
Precision fused quartz and sapphire optical components for laser systems, spectroscopy, vacuum UV optics, and photonic research applications.
Fused Quartz & Sapphire for Optics & Photonics
The optical properties of fused quartz and sapphire — broad transmission potential, low autofluorescence, high hardness or thermal stability, and good polishability — make them common substrate materials for precision optics from deep UV to mid-infrared, depending on grade and specification.
Fused Quartz Optical Properties
| Property | Natural Fused Quartz | Synthetic Fused Silica |
|---|---|---|
| Transmission range | Grade and thickness dependent | Grade and thickness dependent |
| Refractive index (589 nm) | Reference value should be confirmed by material data | Reference value should be confirmed by material data |
| Homogeneity (Δn) | Optical-grade requirement should be specified | Optical-grade requirement should be specified |
| Birefringence (stress) | Annealing and stress review can be discussed | Annealing and stress review can be discussed |
| OH content | Depends on material source and grade | Depends on material source and grade |
| UV transmission | Should be reviewed by wavelength, thickness, and grade | Should be reviewed by wavelength, thickness, and grade |
| Laser damage threshold | Requires application and coating review | Requires application and coating review |
Sapphire Optical Properties
| Property | Value |
|---|---|
| Transmission range | 0.14 – 6.0 μm |
| Refractive index (589 nm) | nₒ = 1.768, nₑ = 1.760 |
| Birefringence | Inherent (uniaxial crystal) |
| Knoop hardness | 1800–2000 |
| Surface finish | Reviewed by optical specification |
| Laser damage threshold | Requires application and coating review |
Key Applications
Excimer Laser Windows & Optics (193 nm, 248 nm)
Synthetic fused silica is the material of choice for DUV optics — its superior UV transmission, low OH-induced absorption, and high laser damage threshold enable use in ArF and KrF lithography illumination systems.
| Specification | Value |
|---|---|
| UV transmission | Reviewed by wavelength, thickness, and grade |
| Homogeneity | Reviewed by optical-grade requirement |
| Birefringence | Stress review can be discussed |
| Surface roughness | Reviewed by optical specification |
| Surface form | Reviewed by optical specification |
IR Spectroscopy Windows (MgF₂ range overlap via sapphire)
Sapphire’s transmission to 6 μm fills the gap between fused silica (cutoff ~3.5 μm) and long-wave IR materials.
- FTIR cell windows: sapphire for aqueous samples (impervious to moisture)
- Mid-IR laser windows: 2.94 μm Er:YAG, 3–5 μm quantum cascade lasers
- Pyrometry: 4–5 μm band temperature measurement
Optical Fiber Preforms
Synthetic fused silica is the base material for silica optical fiber. Tuguan Semiconductor supplies:
- Synthetic silica tubes for Modified Chemical Vapor Deposition (MCVD) preform deposition where specifications fit
- Wet-grade or dry-grade silica options can be reviewed by wavelength and process requirements
- Tube geometry, purity, and documentation should be confirmed before quotation
Vacuum UV (VUV) Optics
Below 200 nm, material grade, thickness, surface condition, and certificate requirements become project-critical. Tuguan Semiconductor can review synthetic fused silica requests for:
- OH content and transmission requirements by wavelength
- Surface roughness targets specified on the drawing
- Transmission documentation requirements when available by material source or inspection scope
Custom Optical Fabrication
We manufacture to customer drawings or specifications:
| Component | Material | Specification |
|---|---|---|
| Windows (flat) | Fused silica / sapphire | Surface finish and flatness reviewed by optical specification |
| Prisms | Fused silica | Angular accuracy reviewed by drawing |
| Rods & cylinders | Fused silica / sapphire | OD tolerance reviewed by drawing |
| Lenses (plano-convex) | Fused silica | Surface form reviewed by optical specification |
| Custom shapes | Both | Per drawing |