How Light affects Orientational Decision-making

摘要

It is an intuitive belief that light has an effect on general wayfinding and path-choosing. Culturally and linguistically, light has been associated with the idea of orientation. "The word 'orientation' comes from orient, or the direction of sunrise, thus orienting oneself means locating east." [de Jesus 1994] In the past, a number of studies have proved, to different degrees, that more people prefer brighter circulation environments, and when give a choice are inclined to go toward the brighter path. In a study on methods of lighting research analysis, Tiller argued that "Research on the behavioral effects of lighting supports the notion that lighting can be used to cue attention, orientation, and wayfinding in humans, ... further studies using a wider range of light levels and additional independent variables are required before firm conclusions about the effects of light level on orientation, wayfinding, and activity level can be drawn." [1990] In lighting design practice, designers very often wash or graze vertical surfaces to accent architectural features. Assuming that this method does draw users' attention to the desired surfaces, quantifying the specific relationships could help the specification process and forming circulation paths with light. This study was to determine a luminance-based scale to which vertical brightness impacts oritentational decision-making. There were two parts to the study: 1. A visualization experiment via an online survey investigating how different vertical luminance ratios of a closer path and a farther path affect which path people choose. 2. A physical room experiment investigating how wall contrast ratio affects people's orientation in a room. The results of the survey showed that when the vertical luminance ratio of the two paths are higher than 1:1.5, most people will choose the brighter path regardless of proximity. This number does not increase with the luminance ratio but is rather an "all-or-nothing" relationship. The results of the physical room experiment showed that a range of luminance ratios could be determined regarding when people prefer to face the brightest wall. Below the range, the contrast is not perceivable enough to make an impact. When the contrast is too extreme, more people will choose a more oblique orientation.