Lighting : Lighting February 2015 - Vol 35 Issue 1
44 LIGHTING MAGAZINE | February/March 2015 RELATING PHOTOCHEMICAL AND PHOTOBIOLOGICAL QUANTITIES TO PHOTOMETRIC QUANTITIES CIE TN 002:2014 Optical radiation has different effects on biological systems. To quantify these effects usually the spectral distribution of a radiant quantity is weighted with the action spectrum of that effect. By this a relation between the photobiological and radiometric quantities is made. In very recent publications, mainly in the field of photobiological safety, a link between an actinic quantity and the corresponding photometric quantity is made mainly to give a simplified risk assessment procedure by means of absolute photometric measurements in combination with relative spectroradiometric measurements instead of absolute spectroradiometric measurements. Unfortunately, different terms or even units are used, e.g. “transformation factor”, “specific effective radiant ultraviolet power”, “proportionality factor”, “WB/lm factor”, or new units are defined, e.g. “Blue Watt”, “WB”. This Technical Note proposes the definition of new terms relating photobiological or photochemical quantities to photometric quantities. It adheres to the correct use of units within the present International System of Units. GUIDANCE TOWARDS BEST PRACTICE IN PSYCHOPHYSICAL PROCEDURES USED WHEN MEASURING RELATIVE SPATIAL BRIGHTNESS CIE 212:2014 ISBN 978-3 -902842-51-0 English, with a short summary in French and German, 65 pages with 13 figures and 12 tables. This report reviews evidence for the procedures and other factors of experiments carried out to investigate relative spatial brightness, making recommendations of those aspects that ought to be considered as essential, or at least desirable, for best practice. These factors include the size and complexity of the visual field employed in trials, evaluation mode (separate, simultaneous, sequential or successive) and experimental biases associated with selection of stimulus range and response mode. Some of the issues raised will be considered, by some, to be obvious and already standard practice: unfortunately such awareness is not widespread. This report hence serves as a guide for those planning experiments to investigate spatial brightness. The proposals are presented as recommendations and not as compulsory. The report identifies those issues for which further research is desirable. CHARACTERISATION OF THE PERFORMANCE OF ILLUMINANCE METERS AND LUMINANCE METERS Joint ISO/CIE International Standard ISO/CIE 19476:2014(E) (former CIE S 023/E: 2013) This joint ISO/CIE International Standard is replacing CIE International Standard CIE S 023/E:2013 without modification of its technical content. The standard defines quality indices characterising the performance of illuminance and luminance meters in a general lighting measurement situation, as well as measurement procedures for the individual indices and standard calibration conditions. Measurements of illuminance or luminance and their accuracy are influenced by various parameters, such as operational conditions, properties of light sources, as well as characteristics of the applied photometers. The characteristics of these photometers alone do not allow the determination of the measurement uncertainty for a specific measurement task. Nevertheless, it is generally true that instruments with “better” characteristics in most cases produce smaller uncertainties than instruments with “worse” properties. This standard has been written to: z give clear and unambiguous definitions for the individual quality indices; z define measurement procedures and methods for numerical evaluation of these quality indices; and z define calibration conditions for illuminance meters and luminance meters. Where different, the definitions of the quality indices and the associated measurement procedures and methods for numerical evaluation given in this standard supersede those given in CIE Publication 53-1982. CIE publication 69-1987 has been superseded by this standard. PHOTOMETRY USING V(λ)-CORRECTED DETECTORS AS REFERENCE AND TRANSFER STANDARDS CIE 210:2014 ISBN 978-3 -902842-50-3 English, with a short summary in French and German, 34 pages with 11 figures. This publication provides recommendations of the CIE concerning the use of V(λ)-corrected detectors as reference and transfer standards for photometric units. Specifically it includes the construction, characterisation and directions for use of standard photometers for such purposes. CIE publications are available from National Committees of the CIE or via the CIE Webshop.
Lighting December 2014 - Vol 34 Issue 6
Lighting April 2015 - Vol 35 Issue 2