Miwako Tokura

Position Index for a glare source located below the line of vision

To measure the difference between sensitivity to glare from a source above the line of vision and that from a source below the line of vision, two subjective experiments were conducted using the adjustment method and the constant method respectively. The sensitivity to the glare caused by a source located below the line of vision was greater than the sensitivity to glare caused by a source located above the line of vision. This tendency was seen especially in elderly subjects. For vertical displacement the difference in sensitivity between sources above and below the line of vision increased with increasing angular distance between the line of vision and glare source.

A pilot experiment on a method for evaluating acceptability of a daylit luminous environment

Abstract 1. 1. We propose a hierarchical model as a hypothesis to evaluate comfort in lighting environments. 2. 2. The model consists of physical quantities such as stimuli, and visual sensations as the first response, and then overall evaluation. 3. 3. A pilot experiment in a side-lit classroom usng 147 subjects was made to examine this model. 4. 4. It was found that in the side-lit classroom the most effective answers for discrimination between “acceptable” and “not acceptable” were “the surface of desk was not considered dark” and “not to experience any reflectance of lighting on the sheet of paper on which they wrote”. 5. 5. Moreover all of the effective items relate to the task area, namely desk and blackboard, and this meant that subjects gave priority to workability in the classroom.