YT308 Telescope Optical Testing Instrument

Overview

The YT308 Telescope Optical Testing Instrument is a precision metrology system engineered for objective, repeatable evaluation of optical transmittance and spectral attenuation characteristics in personal eye protection devices. Designed specifically for quality control laboratories, regulatory testing facilities, and optical safety certification bodies, the instrument operates on the principle of collimated beam spectrophotometry—measuring wavelength-resolved transmission (typically 200–780 nm) through lens samples under defined angular and irradiance conditions. Its core function is to verify compliance with internationally recognized optical safety standards, particularly EN 1836:2015+A1:2022 for sunglasses and EN 166:2022 for personal eye protectors. The system integrates a stabilized deuterium-halogen light source, a monochromator-based optical path, and a calibrated silicon photodiode detector array to deliver high-fidelity spectral data traceable to NIST-certified reference standards.

Key Features

• Automated spectral acquisition across 200–780 nm range with ≤1 nm wavelength resolution and ±0.3 nm accuracy
• Dual-standard validation mode supporting simultaneous EN 1836 and EN 166 test protocols—including UV cutoff verification, luminous transmittance (T_v) calculation, and blue-light hazard assessment (B(λ))
• Motorized sample stage with precise XYZ positioning and angular alignment capability (±0.1° repeatability) to accommodate curved lenses and frame-mounted optics
• Integrated stray-light suppression architecture meeting ISO 9050:2003 requirements for optical transmittance measurement uncertainty
• Rugged, temperature-stabilized optical bench (±0.5°C control) minimizing thermal drift during extended calibration or batch testing
• Compliance-ready reporting engine generating audit-trail logs compliant with ISO/IEC 17025:2017 documentation requirements

Sample Compatibility & Compliance

The YT308 accommodates plano and curved lens substrates up to Ø80 mm diameter and 25 mm thickness, including polycarbonate, CR-39, glass, and photochromic materials. It supports both loose-lens and mounted-frame configurations via adjustable clamping fixtures. All measurement procedures adhere strictly to the geometric and photometric conditions specified in EN 1836 Annex B (sunglasses classification) and EN 166 Clause 7 (optical requirements for protective eyewear). The instrument’s spectral weighting functions are preloaded with CIE standard observer curves (1931 2°) and photopic luminosity function V(λ), ensuring full alignment with EN standards’ photobiological safety calculations. Optional calibration kits include NIST-traceable neutral density filters and certified reference lenses for periodic verification per ISO 17025 clause 6.5.

Software & Data Management

The YT308 is operated via the standalone Windows-based OptiTest Suite v4.2 software, which provides role-based user access control, electronic signature support, and full 21 CFR Part 11 compliance for regulated environments. Data files are stored in encrypted SQLite databases with immutable audit trails recording operator ID, timestamp, instrument configuration, raw spectra, and pass/fail determinations per test parameter. Export options include PDF reports (EN-compliant format), CSV spectral data, and XML metadata compatible with LIMS integration. Software updates are delivered via secure HTTPS channel with SHA-256 integrity verification. Calibration history, maintenance logs, and inter-instrument comparison records are retained for ≥10 years as required under GLP and GMP quality systems.

Applications

• Pre-market conformity assessment of sunglasses against EN 1836 categories (0–4) based on T_v, UV transmission limits, and homogeneity criteria
• Verification of impact-resistant eyewear per EN 166 mechanical and optical requirements, including prismatic deviation and refractive power tolerance checks
• Batch release testing in OEM manufacturing facilities producing certified PPE for occupational safety markets
• Third-party accreditation testing for CNAS, UKAS, and DAkkS notified bodies conducting EN certification audits
• Research applications in ophthalmic optics, including spectral filtering efficacy studies and aging-induced transmittance degradation analysis

FAQ

Does the YT308 support automated pass/fail judgment according to EN 1836 classification tables?

Yes—the software applies real-time spectral integration and category assignment logic per EN 1836 Table 3, flagging deviations in UV-A/B cutoff, luminous transmittance thresholds, and spectral uniformity.
Can the system be used for non-EU standards such as ANSI Z80.3 or AS/NZS 1067?

While not preconfigured for these standards, the raw spectral data export enables post-processing using external algorithms; custom protocol modules may be developed under ISO/IEC 17025 method validation guidelines.
Is external calibration required, and how frequently?

Annual calibration by an ISO/IEC 17025-accredited provider is recommended; internal verification using supplied reference filters should be performed before each testing shift.
What environmental conditions are required for optimal operation?

Ambient temperature: 20–25°C ±1°C; relative humidity: 30–60% RH; vibration-isolated optical table recommended; no direct sunlight or strong EMI sources within 1 m.