Preference for luminance uniformity of refrigerator lighting

Abstract

We investigated minimally required uniformity of refrigerator lighting for comfortable use while maintaining the perceived lighting quality. Two experimental conditions were set depending on having or not having the storage items. In both conditions, 12 luminance uniformity levels were provided in a refrigerator. A total of 33 women participated and assessed the lighting stimuli to judge the perceptibility and acceptability of the presented uniformity levels. As a result, the stored items influenced both the perceptibility and acceptability of the luminance uniformity. To be specific, at least 71% luminance uniformity is recommended to be acceptable, and 80% luminance uniformity is recommended to be perceived as homogeneous for refrigerator lighting. The empirical result conforms to the uniformity guideline of 70% as the minimum, implying it as a minimally requested uniformity of spatial lighting to be considered in lighting design.