Fig. 1
From: Effect of quantity and intensity of pulsed light on human non-visual physiological responses
Layout of the experiment. An integrating sphere with light-emitting diodes (LEDs) was used as the lighting device, and the irradiance of lights was controlled by a computer programme. Participants sat on a chair with their heads facing a diffusion panel, which was located in front of the integrating sphere. Pupil diameter was measured in the left eye using an EMR-8 eye-tracking system with an infrared camera (Nac Image Technology, Inc., Japan)