Quality indexes for road lighting: a review

摘要

The scientific literature in public lighting contains a number of theoretical models to assess the quality of lighting installations. Engineers also use normative and state-of-the-art documents in order to achieve a given quality level. Such variety of models and practices may raise some questions. We make an overview of the theoretical models on which road lighting quality indexes are currently based, as well as some normative procedures and recommended practices. We try to point out their theoretical background and their purpose. This rapid overview leads us to separate 4 levels in the engineering process of building a quality index for road lighting applications. The first level is the functional one: the main objective of the lighting installation (e.g. road safety) must be specified. The second level is that of the task: once the objective is set, a corresponding visual task (e.g. target detection) must be identified. The third level is to collect vision science data in order to make a vision model of the task, and of the appropriate thresholds. The fourth level is the operational one: a measurement method must be defined, based on the vision model, for the actual assessment of the quality index of road lighting installations.