NIM-2 Standard Spectrophotometric Transmittance Measurement System for Ophthalmic Lenses
| Origin | China |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Origin Category | Domestic (PRC) |
| Model | NIM-2 |
| Pricing | Upon Request |
Overview
The NIM-2 Standard Spectrophotometric Transmittance Measurement System is a metrologically traceable instrumentation platform developed by the National Institute of Metrology (NIM), People’s Republic of China. Engineered for precision optical characterization in ophthalmic quality assurance and regulatory compliance laboratories, the system implements double-beam spectrophotometric measurement principles to determine center-point transmittance of finished ophthalmic lenses across ultraviolet (UV-B: 280–315 nm; UV-A: 315–380 nm) and visible (380–780 nm) spectral regions. Its optical architecture incorporates thermally stabilized tungsten-halogen and deuterium light sources, a high-resolution monochromator with <2 nm spectral bandwidth, and a calibrated silicon photodiode detector referenced against NIM’s primary standard irradiance scale. Designed explicitly for lens-centric evaluation—rather than flat-sample transmission—the NIM-2 integrates a motorized lens positioning stage with real-time beam alignment feedback to ensure consistent illumination of the geometric center of curved, high-diopter, and coated optics under standardized collimated beam geometry per ISO 8980-3.
Key Features
- Metrological traceability to NIM’s national optical radiation standards, with expanded uncertainty of ≤1.0% (k = 2) over 280–780 nm
- Compliance with JJF 1106–2003 “Calibration Specification for Transmittance Measurement Devices for Eyewear Products” as a reference-grade verification system
- Automated centering mechanism accommodating spherical, aspheric, and toric lenses up to ±12.00 D, including anti-reflective, photochromic, and polarized coatings
- Double-beam optical path with real-time baseline correction to minimize drift from thermal or source instability
- Integrated 3-axis motorized lens holder enabling repeatable axial positioning within ±10 µm tolerance
- Pre-aligned collimated beam (f/10 geometry) meeting ISO 8980-3 requirements for angular acceptance and stray-light control
Sample Compatibility & Compliance
The NIM-2 supports measurement of all categories defined in GB 10810.3 and ISO 8980-3: uncut ophthalmic blanks, finished single-vision and progressive addition lenses, prescription sunglasses, driving lenses, and occupational safety eyewear. It accommodates plano to ±12.00 D spherical equivalents, base curves from 4.00 to 10.00 D, and maximum diameters of 80 mm. Lens mounting does not require cutting or flattening—curvature is preserved during measurement. The system satisfies metrological requirements for type testing, batch release, and calibration laboratory accreditation under CNAS-CL01 (equivalent to ISO/IEC 17025), and provides documented evidence suitable for GLP/GMP audits and regulatory submissions to NMPA or international authorities referencing ISO 8980 series standards.
Software & Data Management
The proprietary NIM-Transmit v3.2 software runs on Windows 10/11 x64 platforms and provides full 21 CFR Part 11–compatible audit trail functionality—including user authentication, electronic signatures, version-controlled method templates, and immutable raw-data archiving. It automates spectral acquisition, calculates weighted transmittance values per ISO/CIE photopic luminosity function, derives relative visual attenuation factor Q (per ISO 14889), and generates compliant reports with embedded uncertainty budgets. All spectral datasets are stored in vendor-neutral CSV and XML formats, supporting integration into LIMS environments via OPC UA or RESTful API extensions. Calibration certificates, instrument logs, and measurement history are indexed with timestamped digital signatures and SHA-256 hash verification.
Applications
- Verification of UV-blocking performance for ISO 12312-1–compliant sunglasses and driver’s lenses
- Batch conformance testing of anti-reflective coating efficacy across visible and UV bands
- Development and validation of photochromic lens kinetics under standardized illuminants
- Reference measurements for inter-laboratory comparison studies organized by national metrology institutes
- Supporting technical documentation for CE marking, FDA 510(k), or NMPA registration dossiers
- Calibration of routine production spectrophotometers used in lens manufacturing QA labs
FAQ
Does the NIM-2 comply with international regulatory frameworks for medical device optics?
Yes—the system’s measurement protocol, uncertainty budget, and reporting structure align with ISO 13485 quality management requirements and support conformity assessments under MDR Annex II and IV for Class I/IIa ophthalmic devices.
Can it measure lenses with complex multilayer coatings without interference artifacts?
Yes—its double-beam design with wavelength-synchronized referencing and optimized stray-light suppression (<0.01% at 340 nm) ensures accurate transmittance quantification even for broadband AR stacks and dichroic filters.
Is operator training and NIM traceable calibration included with delivery?
Delivery includes on-site installation verification, operator certification training, and a NIM-issued calibration certificate valid for 12 months, with optional annual recalibration services traceable to NIM’s primary standard facility in Beijing.
