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Minutes of the meeting


May 18, 2006


10:00-12:00 a.m.


National Research Council Canada, Ottawa


Liisa Halonen
Marjukka Eloholma
Teresa Goodman
Francoise Viénot
Ken Sagawa
Osvaldo da Pos
János Schanda
Miyoshi Ayama
Sharon McFadden
Joanne Zwinkels
Paula Alessi
Gerhard Rösler
Eugenio Martinez-Uriegas
Yasuhisa Nakano
Dennis Couzin
Andy Jackson
Hirohisa Yaguchi






1. Opening of the meeting

Liisa Halonen opened the meeting and welcomed all to the 3rd meeting of TC1-58. She reviewed the outcomes of the previous TC1-58 meetings. In the 1st meeting in Tokyo (June 10, 2004) the new terms of reference were agreed. In the 2nd meeting in León (May 17, 2005) the TC working programme (tasks and schedule) was defined. The aim of the 3rd meeting is to introduce the TC work done so far, decide on further collection and analysis of existing data and decide on further generation and analysis of new data.

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2. Noting the TC members and introducing the participants

A list of the current TC members was viewed. There are currently 26 members in the TC (Attachment 1). The participants introduced themselves.

3. Apologies for absence

Apologies for absence had been received from: Colette Knight Netherlands, Larry Leetzow USA, Ian Lewin USA, Peter Bodrogi HU, Bill Simpson CAN, Gunther Heidel Germany, Gunilla Derefeldt Sweden, Edward Yandek USA, Malcolm Nicholson UK, Amy Wang China, Chen Dahua China.

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4. Approval of the Agenda

The Agenda was approved.

5. Presentation of recent mesopic research work

Two presentations were given of recent research work done in the mesopic field.

  • Francoise Viénot gave a presentation "Principles of mesopic vision".
  • Marjukka Eloholma gave a presentation "Analysis of performance based mesopic models based on new data sets" (slides in Attachment 2 ).

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6. TC Working programme

The TC working programme was reviewed. There are 3 subtasks in the TC work:

  1. Define mesopic visual performance and related terms
  2. Investigate performance based photometry in the luminance region below approximately 10 cd/m2
  3. Propose a model for the basis of performance based mesopic photometry

In the last meeting the different mesopic applications and the responsible persons and co-workers for each application we named. Helsinki University of Technology HUT (FIN) is responsible for the application road and street lighting. HUT has conducted two surveys in the TC work. The first collected recent and ongoing mesopic research works. The second survey collected experts’ views on the definition of visual performance and related terms, this is related to the subtask 1 above.

The surveys were presented. Answers to the first survey were received from 22 people in 11 countries. As a result, 80 publications related to previous and ongoing mesopic studies were listed as well as 200 other mesopic publications. The survey revealed that there are several interesting research works going on in the mesopic field world-wide. There are at the moment several PhD works going on in the mesopic field. The challenge for TC1-58 is to identify and collect all these PhD-workers to get comprehensive and newest data for developing mesopic photometry.

The second survey was made to outline the opinion of experts in the lighting field on the definition of visual performance and related terms. Answers from 15 people from 10 countries were received. The criteria for being mesopic, the critical visual tasks and parameters were asked in the survey. In defining the critical visual tasks driving performance was emphasized by the experts. For further defining the visual tasks the following approaches were suggested: task analysis, gathering luminance data of real environments in driving and outdoors, analysis of eye-tracking data and evaluation of driver performance under dynamic conditions. The survey results were discussed. It was proposed not to make the TC work too wide and to use the data of the second survey in defining the relevant visual tasks and parameters.

Related to the subtask 2 of the working programme, HUT has done experiments on reaction time and contrast threshold and applied the new data sets to the X-model and MOVE-model (Attachment 3). HUT will continue to generate new data-sets with different parameters and apply these to the existing models. HUT will also collect luminance data from road lighting and driving situations. This is to get data on the visual tasks and their parameters, for example the contrasts found in driving conditions. No other new data was reported. Liisa Halonen informed that all the TC members will be contacted after the meeting to ask for their possibility to generate new data for testing and analysing the existing performance based mesopic models.

The objective of the TC is to come to conclusion on proposing a model for performance based mesopic photometry by June 2008.

7. Closure of the meeting

Liisa Halonen closed the meeting and thanked all the participants for a very good and fruitful meeting.

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