The BPC300 spectrophotometer offers accurate characterisation of photochromic (photosensitive) lens transmission in the faded and AM2 conditioned states.
The fully automated BPC300 enables product testing of prescription and non-prescription sunglasses in accordance with international standards, and the development of photochromic formulations.
The versatile BPC300 permits darkening and fading-back kinetic studies, whilst the modification of sample temperature, conditioning beam illuminance and spectrum accounts for a broad range of lens exposure conditions. An optional polarising lens capability is on offer for the extension of the measurement scope.
Core benefits
- Accurate transmission testing of photochromic lenses
- Explore lens performance in range of conditions
- Monitor rates of darkening and fading
- Easy and highly repeatable process
Features
- Monochromator based, collimated tuneable light source (280-780nm)
- Temperature-controlled water bath with mount for plano lens sample
- AM2 conditioning beam (including facility to attenuate and filter spectrum)
- Optically chopped monochromatic beam with lock-in signal recovery enables measurement under AM2 activation
- Automated reference level measurement
- Fully-automated by Windows application including establishment and running of pre-defined measurement profiles
- Generation of measurement report including parameters required by standards
Applications
- ISO/ EN 8980-3:2013 - "Ophthalmic optics. Uncut finished spectacle lenses. Transmittance specifications and test methods."
- ISO/ EN 12312-1:2013 - "Eye and face protection. Sunglasses and related eyewear. Sunglasses for general use."
- ANSI Z80.3: 2015 - "Non-prescription Sunglass and Fashion Eyewear Requirements."
- A S/NZS 1067-2016 - "Sunglasses and fashion spectacles."
Reported Parameters
- τV0 : Luminous transmittance in the faded state at (25±2)°C
- τV1 : Luminous transmittance in the darkened state at (25±2)°C
- τV0 /τV1 : Photochromic Response
- Lens category
- Colourimetric parameters: CIE 1931 & CIE Lab
- τSUVA : Mean UVA spectral transmittance weighted by AM2
- τSUVB : Mean UVB spectral transmittance weighted by AM2
- Qsign : Visual attenuation coefficient for red, green, blue and yellow incandescent
- τsb : Solar blue light transmittance
- The rate of darkening and fading at a single wavelength
Optional reports include:
- τVW : Luminous transmittance at (5±2)°C
- τVS : Luminous transmittance at high temperature (35±2)°C
- τVA : Luminous transmittance at reduced solar simulator level and (25±2)°C