UV-grade fused silica optical windows engineered for demanding applications from deep UV to near-infrared. High laser damage threshold, excellent thermal stability and superior surface quality for laser systems, semiconductor equipment and scientific instruments.
When specifying this product, these parameters most directly impact performance and cost:
| Material | UV Fused Silica (SiO₂) |
| Transmission Range | 185 – 2,500 nm |
| Diameter Range | Custom / 3mm – 200mm |
| Thickness Range | Custom / 0.5mm – 50mm |
| Surface Quality | 10-5 / 20-10 / 40-20 (MIL-PRF-13830B) |
| Surface Flatness | λ/10 / λ/20 per inch @ 632.8nm |
| Coating | AR / HR / BBAR / Custom |
| Clear Aperture | ≥90% |
| Parallelism | < 3 arc-sec (precision) / < 1 arc-min (standard) |
| LIDT | > 10 J/cm² @ 1064nm, 10ns (AR coated) |
Parameter Reference Guide
Typical Standard capability — available as shown
Available Alternative options exist — request quotation
Custom Per your drawing — quote after review
Subject to Review Depends on project specifics
Select the optimal optical material based on your wavelength, power, thermal environment and mechanical requirements.
Select the optimal substrate material based on your wavelength, environment, and budget requirements.
Not sure which material to choose?
Ask AI Optical EngineerCoatings are engineered around your specific wavelength and operating conditions.
We optimize specifications to match your system requirements — not over-specify. Tighter tolerances increase cost without always improving system performance. Our engineers will work with you to identify which parameters actually matter for your application and where standard tolerances are sufficient. Typical manufacturing capabilities:
Every component undergoes 100% inspection before shipment. We provide full inspection documentation including interferometer reports, spectral transmission curves, surface quality images and dimensional measurement data. Equipment capabilities:
Thermal management: Fused silica has near-zero thermal expansion (CTE ≈ 0.55 × 10⁻⁶/K), making it ideal for environments with temperature variation. However, at high average powers, even small absorption in coatings can cause thermal lensing.
LIDT considerations: Always specify your laser wavelength, pulse duration, repetition rate and beam diameter. Laser-induced damage threshold depends on all of these. A coating optimized for 355nm CW may fail at 355nm pulsed.
Surface quality vs. cost: 10-5 scratch-dig is needed for high-precision imaging and laser cavities. For simple protective windows, 60-40 is sufficient and significantly less expensive.
Wedging: For laser cavity windows, specify wedged windows (typically 0.5°–3°) to eliminate etalon effects that cause power instability.
Use this quick decision guide to confirm whether fused silica is optimal, or whether you should consider an alternative material.
| Your Requirement | Best Material | Why |
|---|---|---|
| Need UV transmission (< 350nm) | Fused Silica ✓ | Fused silica transmits down to 185nm. Ideal for UV. |
| Visible-NIR only (350-2000nm) | Nbk7 | N-BK7 is more economical for visible-NIR. No need to pay for UV capability. |
| Need IR beyond 4.5um | Znse | Fused silica cuts off at 2.5um. Use ZnSe for mid-IR or LWIR applications. |
| Your Requirement | Best Material | Why |
|---|---|---|
| High-power laser (> 50W CW) | Fused Silica ✓ | Low thermal expansion and high LIDT make fused silica the standard for high-power laser windows. |
| Low-power or non-laser | Nbk7 | For non-laser or low-power applications, N-BK7 provides adequate performance at lower cost. |
| Your Requirement | Best Material | Why |
|---|---|---|
| Extreme scratch resistance needed | Sapphire | If the window will be exposed to abrasive particles or frequent cleaning, sapphire (Mohs 9) outperforms all glass. |
| Standard indoor/cleanroom | Fused Silica ✓ | For controlled environments, fused silica provides excellent performance without the premium cost of sapphire. |
The following documentation is available upon request for qualified engineering projects:
CAD & dimensional specs per your requirements
Material properties, transmission curves & certificates
Spectrophotometric measurement data
Surface quality, flatness, centration & dimensional data
CoC with full traceability per project requirements
Application-specific specification documentation
Documentation availability depends on project scope and order quantity. Request details during RFQ.
To help us provide an accurate quotation, please prepare the following information. Not all fields are required — send what you have, and our engineering team can help identify missing parameters.
Not sure about some specifications? Send what you have — our engineering team will help identify the missing parameters and recommend appropriate values for your application.
When requesting a quote, please provide the following information:
Contact us for exact pricing based on your specifications.
Specification Parameters
Typical Specifications shown on this page are standard capabilities. Available Options include alternative materials and coatings. Custom Specifications are available per your drawing. Requirements beyond standard capability are marked Subject to Engineering Review.
When requesting a quote for optical windows, providing the following information helps us give you an accurate quotation:
Tell us your wavelength, application and operating conditions. PhotonEdge AI Optical Engineer can help you identify the key specifications before you request a quote.
Ask AI Optical Engineer Request a QuoteTell us what you know. We'll help identify what you still need.
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