BPC300 Photochromic Lens Spectrophotometer

  • BPC300 Photochromic Testing System
  • BPC300 Photochromic Testing System
  • Transmission Measurement of Photochromic Lens
  • BPC300 Optical Probe
  • BenWin+ Software Screenshot

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


  • 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


  • 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


Spectral range of operation 280-780nm
Bandwidth 5nm
Wavelength accuracy ± 0.1nm (2400g/mm), ± 0.2nm (1200g/mm)
Beam diameter at sample plane 4mm diameter
Measured transmission range 0.5-100%
Maximum sample diameter 75mm
Conditioning beam AM2 with requirements of ISO8980-3:2013
Optional filtering
Temperature range 5-50°C
Temperature accuracy ± 0.2°C
Bench space required 1m deep x 2.5m wide
Services requirements 6 x main sockets 1200W power consumption
Nitrogen gas supply where measurements below ambient are required

Monochromatic Probe Source

UV source 30W Deuterium lamp
UV-Vis source 100W Quartz Halogen lamp
Monochromator configuration Symmetric, single Czerny-Turner
Monochromator focal length 300mm
Diffraction gratings 2400 & 1200 g/mm
Diffraction grating mount Triple grating turret
Dispersion 5.4nm/mm (2400g/mm)
Bandwidth 5nm
Wavelength accuracy ± 0.1nm (2400g/mm)
± 0.2nm (1200g/mm)
Chopping frequency 175 Hz (typical)
Beam diameter at sample plan 4mm diameter

Water Bath

Temperature range 5-50°C
Temperature accuracy ±1°C

Conditioning Beam

Spectral match AM2 with requirements of ISO8980-3:2013
Beam illuminance 0-50klx
Beam filtering Optional filtering

Computer requirements

OS Windows 7, Windows 8 (32-/64-bit) operating systems (or newer)
Software control BenWin+ Spectral acquisition software
Minimum hard disk space Approx. 100MB
Minimum RAM 2 GB
Interface 4 x USB 2.0 ports


BPC300 Photochromic lens spectrophotometer
BPC300_POLARISE Polarised lens testing add-on to BPC300

Ordering information

BPC300 Photochromic lens spectrophotometer
BPC300_POLARISE Polarised lens testing add-on to BPC300
09101 Replacement 100W QTH Lamp
27441 Replacement 30W Deuterium lamp
19084 Replacement 150W Xenon Lamp

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