Description

Many industries employ colouring processes to provide products designed to enhance colour uniformity, colour recognition or aesthetic appeal. The producer must deliver a product of the desired colour with its variation controlled to an extent appropriate for the product's use and the customer's expectations. Colour measurement and colour-difference evaluation are essential tools to help manufacturers accomplish these goals with efficient colour production processes. 

Colour-difference evaluation models have been, and continue to be, developed. The CIE, through its technical committees, has periodically established recommended practices for colour-difference evaluation to promote uniformity of industrial practice. The last CIE recommendation on this subject was made in 1978. Accumulated research since then indicates it is now possible to identify a model with improved agreement with visual colour-difference judgements. 

Recommended practice for industrial colour-difference evaluation is presented. The recommended model is an extension of the CIE 1976 (L*a*b*) colour-difference model with correction for chroma-dependent variation in colour-difference perception. Reference conditions define material and viewing environment characteristics to which the colour-difference model applies. Factors are introduced to correct for the parametric effects of various conditions of use. Guidelines for further research on colour-difference perception are given. 

This Technical Report is written in English, with a short summary in French and German, and contains 20 pages. 

Description

This report is a revision and update of CIE 115-1995 "Recommendations for the Lighting of Roads for Motor and Pedestrian Traffic". Since it was issued in 1995 power consumption and environmental aspects have become more important and at the same time, the improved performance of luminaires and lamps, and especially the introduction of electronic control gear, has made it possible to introduce adaptive lighting for roads for motorised traffic, conflict areas and areas for pedestrians. A structured model has been developed for the selection of the appropriate lighting classes (M, C, or P), based on the luminance or illuminance concept, taking into account the different parameters relevant for the given visual tasks. Applying for example time dependent variables like traffic volume or weather conditions, the model offers the possibility to use adaptive lighting systems.

The publication replaces CIE 115-1995 "Recommendations for the Lighting of Roads for Motor and Pedestrian Traffic".