Cosine Corrector FLB1010 by Jingfei Technology

Overview

The Jingfei Technology Cosine Corrector FLB1010 is a precision optical accessory engineered for radiometric and photometric measurement systems requiring compliance with the cosine response law (Lambert’s cosine law). It functions as a diffusing optical element mounted directly in front of a detector—typically a silicon photodiode, spectrometer input fiber, or CCD-based sensor—to reshape the angular responsivity profile of the detection system. Without such correction, most bare detectors exhibit non-ideal angular sensitivity: their output signal deviates significantly from the ideal cos(θ) dependence, especially at incident angles beyond ±30°, leading to systematic underestimation of irradiance or illuminance in hemispherical or wide-field applications. The FLB1010 achieves high-fidelity cosine correction through its precisely engineered matte-black anodized aluminum body and optimized internal geometry, ensuring uniform light scattering across the 0–85° incidence range while minimizing specular reflection and edge diffraction effects.

Key Features

• Optimized cosine response: Validated to meet ISO/CIE Class B specifications for cosine error (±3% deviation within ±60°; <±8% up to ±85°) when paired with standard Si photodiodes.
• Robust mechanical construction: CNC-machined black anodized aluminum housing provides EMI shielding, thermal stability (operating range: −10 °C to +60 °C), and resistance to oxidation and UV-induced degradation.
• Standardized optical interface: SMA905 connector enables direct coupling to spectrometers, fiber-coupled radiometers, and OEM sensor modules without alignment tools or adhesives.
• Compact form factor: 30 mm outer diameter and 18.5 mm total height allow integration into space-constrained optical benches, portable field instruments, and drone-mounted remote sensing payloads.
• Calibration-ready design: Flat, centered 12 mm effective sensing aperture ensures compatibility with NIST-traceable calibration sources and integrating sphere setups per ASTM E308 and CIE S 025/E:2015.

Sample Compatibility & Compliance

The FLB1010 is compatible with detectors having active areas ≤12 mm in diameter and spectral responsivity spanning 250–1100 nm (UV-VIS-NIR). It is routinely deployed with Ocean Insight, Avantes, and Hamamatsu spectrometers, as well as industrial photometers used in LED lighting validation, solar simulator characterization, and daylight harvesting system commissioning. The device complies with core requirements of IEC 62471 (Photobiological Safety), ISO 8995-1 (Lighting of Work Places), and CIE Publication 127 (Measurement of LEDs). Its material finish and dimensional repeatability support GLP-aligned instrument qualification protocols, including IQ/OQ documentation for regulated photometric laboratories.

Software & Data Management

While the FLB1010 is a passive optical component, its integration into measurement workflows benefits from traceable software environments. When used with spectrometers supporting spectral irradiance calculation (e.g., via OceanView or AvaSoft), the cosine correction factor is applied during post-acquisition processing using pre-characterized angular response curves. Jingfei provides optional NIST-traceable angular responsivity datasets (in CSV format) for each FLB1010 batch, enabling users to implement custom correction algorithms compliant with FDA 21 CFR Part 11 audit trail requirements. Firmware-upgradable spectrometers may embed these correction profiles directly into acquisition routines for real-time irradiance normalization.

Applications

• Outdoor solar irradiance monitoring (global horizontal irradiance, GHI) in meteorological networks and PV plant performance ratio analysis.
• LED and OLED display luminance uniformity mapping under variable viewing angles.
• Validation of daylight-responsive building control systems per EN 15232 and ASHRAE 90.1.
• Calibration transfer between laboratory-grade goniophotometers and field-deployable handheld lux meters.
• Biological photostimulation studies where action spectra depend on angularly resolved photon flux density.

FAQ

What is the maximum recommended incident angle for accurate cosine correction?
The FLB1010 maintains ≤±8% cosine error up to ±85° from normal incidence, with optimal performance (≤±3%) within ±60°.
Can the FLB1010 be used with UV-enhanced or thermopile detectors?
Yes—its black anodized surface exhibits stable diffuse reflectance down to 250 nm; for thermopiles, verify thermal mass compatibility with your acquisition dwell time.
Is the SMA905 interface compatible with FC/PC or ST connectors?
No—mechanical adapters are required; direct mating is only supported with SMA905-terminated fibers or sensors.
Does Jingfei provide calibration certificates with each unit?
Batch-level angular responsivity data is supplied; individual unit NIST-traceable calibration is available as an optional service.
How should the FLB1010 be cleaned to preserve optical performance?
Use lint-free wipes moistened with spectroscopic-grade isopropanol; avoid abrasive cleaners or ultrasonic baths to prevent micro-scratching of the diffuser surface.