January 2013: Pro-Lite has completed the installation of the first 3m diameter Labsphere integrating sphere photometer in Europe for exterior lighting specialists, DW Windsor. The sphere is now operating successfully at DW Windsor’s manufacturing facility in Hoddesdon, Hertfordshire. The Illumia® sphere was manufactured by Labsphere Inc and enables DW Windsor to accurately measure the colour and brightness of even the very largest streetlight luminaires.
“Our custom-designed Labsphere integrating sphere puts us in the unique position of having one of the largest and possibly the most accurate systems of its type in the UK,” said Alan Grant, DWW’s Design and Development Director. “Unlike other cube or geodesic shapes or spheres coated in ordinary reflectance paints, our Labsphere system is coated with their special high reflectance barium sulphate sphere paint ("Spectraflect") so we can deliver accurate, repeatable results regardless of the size of the fitting, type of light source or shape of light beam produced.”
Used to measure the luminous flux (lumens), colour temperature and colour rendering of luminaires, the 3m integrating sphere and spectroradiometer is one of the most accurate methods to measure the light output from LEDs, including the very large Solid State Lighting (SSL) luminaires designed for street lighting applications. The Labsphere ILLUMIA sphere supports both 2pi (hemispheric) as well as 4pi flux measurements with the device under test positioned in either a base-up or base-down orientation. Labsphere's LightMtrX software also reports the scotopic and photopic lumens, which allows for the computation of the S:P light ratio as required by BS 5489-1:2012 Code of Practice for Design of Road Lighting and in the ILP’s Professional Lighting Guide, PLG 03 (2012).
With standards such as IES LM-79-08 calling for integrating spheres to be at least fifty times larger in surface area than the luminaire to be measured, a 3m sphere was chosen to ensure good spatial integration and high accuracy with the large outdoor and streetlighting luminaires manufactured by Windsor. The investment in the sphere was considered to be a vital addition to DW Windsor’s photometric laboratory spurred by its on-going commitment to provide accurate luminaire data and to prevent disillusionment with LEDs as a light source.
Click here to go to the DW Windsor web site