Description

The correlation of models fThis volume contains two Technical Reports prepared by Technical Committees within Division 1 and Division 3. 

The Technical Collection is written in English, with short summaries in French and German. 

• CIE 146:2002 CIE Equations for Disability Glare 

Three disability glare equations have been defined to extend the classic Stiles-Holladay equation to take account of the effect of age, the effect of ocular pigmentation and to extend the angular domain over which the equations are valid. They all describe the veiling luminance L veil (in cd/m²:) due to a point glare source at an angle Theta (in degrees) to the line of sight that gives rise to an illuminance E glare (in lx) in the plane of the observer's eye, and they do so with adequate accuracy within their respective validity domains. The CIE Age-adjusted Stiles-Holladay Disability Glare equation has a restricted validity domain of 1° < Theta < 30° that is extended in the low angular region by the CIE Small Angle Disability Glare equation to the domain of 0,1° &let; Theta &let;30°. The CIE General Disability Glare equation further increases the validity domain to the range of 0,1° &let; Theta &let; 100° and also includes an eye pigmentation factor p which plays a role at glare angles greater than 30°. They all include age A (in years) as a factor. The technical report consists of 14 pages with 8 figures. 

• CIE 147:2002 Glare from Small, Large and Complex Sources The UGR, while valid for "normal" sources between 0,005 m² and 1,5 m² assesses "small" sources (<0,005 m²) too severely and is too tolerant for "large" sources (>1,5 m²). This Technical Report gives formulations and recommendations for small and large sources which agree with research results and practical experience. For "complex" sources, such as specular luminaires, it gives a more realistic glare assessment than that based on average luminance over the full luminaire area. The technical report consists of 13 pages with 3 figures and 2 tables. This report is dedicated to the memory of the late Professor Heinrich D. Einhorn. r vision and visual performance

Description

In the framework of a research project on vision models, the visual performance data of different authors have been compared with respect to their relation to background luminance, contrast and size of the critical object. Rea and Ouellette presented a model based on their own data on "Reaction Time", that allows the calculation of Visual Performance (VP) according to their definition for given visual task conditions. However, their definition of VP differed from those used in all of the other studies considered here. 

As part of this research project a model for VP was developed, based on the very comprehensive study of H. C. Weston in 1945. He used, as performance criteria, the speed with which the form of a target could be detected and a term comprising accuracy of recognition. Investigations of Muck and Bodmann, using similar criteria, composed of search time and accuracy, have been compared with the Weston model and showed good agreement. Likewise, the data of Simonson and Brozek, McNelis, Smith and Rea, and Loe and Waters have been examined. 

The differences between the Rea and Weston models can be attributed to the different criteria used for measurements of Visual Performance. In Rea's case, the inverse of the time needed to see a target varying in size and contrast was used as a measure; in Weston's case it was a composite of visual acuity, time and errors made. The differences observed are mainly due to the sensitivity to contrast: Rea's model does not show significant dependency on contrast but Weston's does. 

It became evident that a strong relationship between visual acuity and performance exists. The influence of age on visual acuity was found to be of major importance to Visual Performance also. 

The technical report is written in English, with a short summary in French and German. It consists of 45 pages with 30 figures and 16 tables.