Key Features
- Narrow Spectral Band (200–1200 nm): Precisely engineered UV filters that reject out-of-band wavelengths, enabling accurate ultraviolet detection.
- High Peak Transmission: Optimized thin-film designs deliver high peak transmission in the UV passband, improving detection efficiency.
- Solar-Blind Technology: Effectively suppresses visible and NIR background, ideal for detecting weak UV signals under strong solar radiation.
- Sharp Spectral Transition: UV shortpass filters feature steep cut-off slopes, ensuring high transmission in the passband with excellent blocking beyond it.
- Broad Application Coverage: Widely used in power line corona detection, forest fire monitoring, atmospheric studies, high-voltage equipment inspection, and UV photography.
General Description
Shape Optics Technologies (SOT) develops high-performance solar-blind UV filters operating from 200 nm to 1200 nm, designed for applications requiring high sensitivity UV detection in bright daylight environments.
These UV optical filters combine high peak transmission in the ultraviolet region with strong rejection in the visible and near-infrared, allowing reliable signal discrimination. The result is excellent signal-to-noise performance for demanding UV sensing applications.
SOT UV shortpass filters exhibit a sharp transition between reflection and transmission bands, with uniform spectral performance across the full clear aperture. When paired with UV longpass filters, they can form custom UV bandpass configurations, providing additional flexibility for system designers.
Spectrum Transmission Curves & Customization
Standard spectral transmission curves are available.
If off-the-shelf components are not suitable, custom UV filters can be designed to meet your exact wavelength, bandwidth, slope, and blocking requirements.
Contact us to discuss your application and request custom UV filter solutions.
Coating Quality & Environmental Reliability
All UV filters are qualified to MIL-C-675C and CCC-C-440 standards:
- Adhesion Test: LT-90 tape test, three removals; no blistering or peeling
- Temperature Cycling: −62 ± 1 °C to 71 ± 1 °C; no coating detachment
- Abrasion Resistance: 1.0 lb gauze test, 25 cycles; no surface damage
- Humidity Resistance: 49 ± 2 °C, 95–100% RH for 24 hours; film intact
- Solvent & Cleaning: Acetone and alcohol exposure; no peeling or scratches
- Salt Spray: 100 hours at 35 °C with 5% NaCl; no corrosion or degradation
Standard Specifications
| Parameter | Specification |
|---|---|
| Substrate Material | Fused Silica |
| Diameter Tolerance | +0 / −0.2 mm |
| Thickness Tolerance | ±0.1 mm |
| Clear Aperture | ≥ 80% of diameter |
| Surface Quality | 60-40 scratch & dig |
| Coating Type | Multi-layer dielectric |
| Transmittance | ≥ 85% |
| Spectral Slope | 90% → 10% < 10 nm |
| Blocking | OD > 4 |
| Operating Temperature | −40 °C to +60 °C |
Applications
Solar-blind UV filters and UV shortpass filters are widely used in:
- Corona Detection on Power Lines – Detection of UV emissions from electrical discharge
- High-Voltage Equipment Monitoring – Identifying arcing and sparking events
- Forest Fire Monitoring – Early detection via UV radiation signatures
- Atmospheric Studies – UV radiation analysis and sensing
- UV Photography – High-efficiency ultraviolet imaging
SOT Strengths & Capabilities
SOT is a trusted provider of precision UV optical filters, combining advanced thin-film coating technology, strict military-grade testing, and custom engineering capability. Our solar-blind UV filters are designed for industrial, scientific, and environmental monitoring applications, delivering reliable performance even in harsh operating conditions.
Standard UV Filter Products
UV Bandpass Filter Range
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Center Wavelengths: 214–380 nm
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Peak Transmittance:
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214–220 nm: >10%
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230 nm: >12%
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254–260 nm: >15%
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280–297 nm: >20%
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340–380 nm: >30%
-
-
FWHM: 8–25 nm
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Blocking Range: 200–1100 nm (OD2–OD5)
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Sizes: 2–50 mm
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Clear Aperture: Φ2–Φ50 mm
Stock UV Shortpass Filters
| Description | Cut-off (nm) | Thickness (mm) | Item No. |
|---|---|---|---|
| UV Shortpass Filter | 265 | 1 | XUS0265 / ZUS0265 |
| UV Shortpass Filter | 300 | 1 | XUS0300 / ZUS0300 |
| UV Shortpass Filter | 325 | 1 | XUS0325 / ZUS0325 |
| UV Shortpass Filter | 350 | 1 | XUS0350 / ZUS0350 |
| UV Shortpass Filter (High-Spec) | 350 | 1 | XHS0350 / ZHS0350 |
| UV Shortpass Filter | 385 | 1 | XUS0385 / ZUS0385 |
| UV Shortpass Filter (High-Spec) | 385 | 1 | XHS0385 / ZHS0385 |
| UV Shortpass Filter | 400 | 1 | XHS0400 / ZHS0400 |
Custom configurations are available upon request.