وحدة لوحة PCBA لمحاكاة الطاقة الشمسية LED 200-1750 نانومتر
The primary wavelengths for الأشعة تحت الحمراء ذات الموجة القصيرة (سوير) المصابيح in biometrics و identity authentication range from 1050nm to 1550nm. The industry gold standards are 1310نانومتر و 1450نانومتر.
Biometric system developers select these specific SWIR bands due to their unique tissue penetration depth, water absorption spectrum properties, and high eye safety margins.
1. Core SWIR Wavelengths and Biometric Applications
1310nm LED: Subcutaneous Vein Recognition & Dermal Biometrics
- Target Applications: Palm vein recognition, 3D face identification, advanced fingerprint anti-spoofing systems.
- Technical Breakdown: The 1310nm spectral band sits within a low-absorption window for water but features high contrast for deoxygenated hemoglobin. This allows the SWIR light to penetrate deep into the dermal layer, capturing ultra-high-resolution subsurface vascular patterns that are impossible to clone or forge.
1450نانومتر / 1470nm LED: Anti-Spoofing & Liveness Detection
- Target Applications: High-security facial liveness detection, presentation attack detection (PAD), multispectral skin mapping.
- Technical Breakdown: The 1450nm wavelength matches the peak water absorption spectrum. Human skin contains high moisture content, which strongly absorbs 1450nm light, appearing dark on SWIR cameras. Conversely, fake materials (synthetic silicone masks, 3D-printed models, high-res photos) lack active moisture and reflect the light, appearing bright. This spectral difference instantly detects presentation attacks.
1050نانومتر / 1200nm LED: Multispectral Iris & Face Fusion
- Target Applications: Dual-mode iris scanning, cross-border border control gates, cost-effective multimodal biometrics.
- Technical Breakdown: 1050nm acts as the transition wavelength between Near-Infrared (نير) and Short-Wave Infrared (سوير). Standard Silicon CMOS image sensors retain quantum efficiency at 1050nm. It allows systems to gain deep tissue penetration benefits without upgrading to expensive Indium Gallium Arsenide (InGaAs) cameras.
1550nm LED: Long-Range Surveillance & Ambient Light Immunity
- Target Applications: Distance-based airport facial recognition, in-cabin driver monitoring systems (DMS), outdoor biometric gates.
- Technical Breakdown: 1550nm is a designated eye-safe wavelength. The human cornea and lens absorb this light before it reaches the retina, allowing for much higher permissible optical output power. Additionally, solar irradiance drops significantly at 1550nm, eliminating background noise caused by direct sunlight during outdoor biometric scanning.
2. المقارنة الفنية: NIR vs. SWIR in Biometric Security
| ميزة | NIR LED (850نانومتر / 940نانومتر) | SWIR LED (1050نانومتر – 1550نانومتر) |
|---|---|---|
| Anti-Spoofing Capability | Vulnerable to ultra-realistic 3D silicone masks and high-definition screen replays. | Extreme. Instantly exposes synthetic materials using moisture-absorption signatures. |
| Dermal Penetration | Shallow penetration; limited to surface-level epidermis features. | Deep. Reaches deep subcutaneous layers to read hidden vascular anatomy. |
| Solar Noise Resistance | High interference under direct sunlight; requires complex optical filtering. | Excellent. Natural sunlight has minimal energy in the 1310nm/1550nm bands. |
| Eye Safety Limit | Heavily restricted power output to prevent permanent retinal damage. | High Margin. Safe for continuous, high-power long-range illumination. |
