Lighting efficiency under mesopic photometry conditions

A Practical Model for Mesopic Photometry

This article reports the results of a multinational research project investigating visual performance in halflight (mesopic) conditions. From the experimental investigations using reaction time, detection threshold and recognition contrast threshold techniques, the results were used to develop a system for practical mesopic photometry, which provides an acceptably good fit to the experimental d...

Mesopic luminance assessed with minimum motion photometry.

We measured the relative contribution of rods and cones to luminance across a range of photopic, mesopic, and scotopic adaptation levels and at various retinal eccentricities. We isolated the luminance channel by setting motion-based luminance nulls (minimum motion photometry) using annular stimuli. Luminance nulls between differently colored stimuli require equality in a weighted sum of rod an...

Development of Visual Performance Based Mesopic Photometry

This work started by investigating the applicability of the photopic V( ) function to predict visual task performance at mesopic light levels. Visual acuity and pedestrian visibility experiments were carried out in varied lighting and viewing conditions. The results indicated the inadequacy of photopic photometry to characterise the response of peripheral vision at low mesopic light levels. The...

Pupil location under mesopic, photopic, and pharmacologically dilated conditions.

PURPOSE To determine whether there are systematic changes in pupil location with changes in the state of pupil size and with other ocular variables. METHODS High-resolution images of the pupil of the eyes of 70 subjects were taken using an infrared-sensitive camera. Images were obtained under mesopic, photopic, and pharmacologically dilated conditions. From the images, the center and diameter...

Skin Colour Detection Under Changing Lighting Conditions