Compare and contrast on varied Illuminance meters

Abstract

Light is an important cue for visual field on human visual and psychological perception. A common device used for assess quantity of light in lighting study is an illuminance meter. The models of the device cost widely from thousand to hundred thousand Thai Baht. The meter can be different
because of the model specification and accuracy. The accuracy of light measurement depends on three sets of factors: (1) accuracy of the instrument; (2) calibration of the instrument; and (3) errors in use. At a large university in north-eastern Thailand, there are various lighting instruments for study and research. Since the meters are various models and aged, they provide different measured values when reading at the same spot and time. Thus it is necessary to show the difference of the reading and suggest some variable to adjust. This study investigated the difference found from various meters.