ACTIVITY REPORT DIVISION 1 - cie

Terms of Reference:
With several new mesopic photometry investigations being contemplated, the impact of theory
of other considerations on the experimental design will be reported.
Report:
No update.
R1-35 (V) Irregularities in y - 10(λ) : P Walraven NL
Year Established: 2004
Terms of Reference:
To document the irregularities in y - 10(λ) and, if necessary, to recommend the formation of a
Technical Committee to consider possible modifications.
Report:
No progress has been made since the last report.
R1-36 (V) Action Spectra for Glare: J Fekete HU
Year Established: 2004
Terms of Reference:
To summarize the literature on the subject and make recommendation for terms of reference
for a technical committee.
Report:
Introduction
One of the special feats of human vision is the ability to see well in lighting that ranges from
moonlight to bright sunlight: almost a thousand-million-fold change in light level. It is no
wonder that the eye remains past compare by any physical detector of light in yielding
appropriate vision over a range that bridges about nine units on a logarithmic scale.
As humans obtain approximately 90% of information by means of visual perception, good
visibility is particularly important when driving a motor vehicle. Poor visibility conditions
result in a lack of information for drivers.
Night-time driving is a situation that takes place under changing mesopic conditions. Vehicle
headlamps illuminate a small part of the visual field, and the headlamps of approaching
vehicles modulate the state of adaptation of the driver continuously in a very unpredictable
way, as well as causing glare for the driver.
The present report summarizes literature data (in 2007) on interrelationship between visibility
and produced glare.
Papers presented during the past year
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