Effects of illuminance levels of solid state lighting sources on visual comfort

Lighting systems in interior architecture need to be designed according to the function of the space, user's comfort and needs. In order to see the environment, besides light and reflecting surfaces, desired lighting levels are required for visual comfort. Desired and comfortable lighting levels increase task efficiency. The aim of this study is to research the effects of illuminance levels on user's visual comfort and reading performance. Therefore, with the participation of eighty participants from the department of Interior Architecture of Çankaya University, six lighting scenarios were created with LED and OLED lighting sources that consisted of three different illuminance levels. A reading task was performed in each lighting scenario. The results indicated that the illuminance level of 500 lux was visually more comfortable than the other illuminance levels. Different illuminance levels were found to be more comfortable for different visual comfort criteria. OLED lighting was found visually more comfortable than LED lighting with respect to the visual comfort criteria. In addition, participants read slower under the illuminance level of 800 lux for each lighting source and it was concluded that illuminance levels effect user's visual comfort and reading performance. Keywords: Illuminance Levels, LED, OLED, Reading Performance, Visual Comfort