CircadianVisor: Image Presentation with an Optical See-Through Display in Consideration of Circadian Illuminance

In modern society, the impact of nighttime artificial lighting on the human sleep/wake cycle (the circadian rhythm), has long been an important issue. In augmented reality, such health hazards should be prevented if we are to become a society that wears optical see-through head-mounted displays (OST-HMDs) on a daily basis. We present CircadianVisor, an OST display system that controls circadian performance. Our system combines an OST-HMD with a liquid crystal (LC) shutter and a spectrometer to control the circadian illuminance (CIL, biolux) of light incident on the user’s eyes. To prevent the CIL at the eyes from exceeding the threshold, correct for the displayed image based on RGB values, and adjust the transmittance of the LC visor to pass through the environment light based on spectral measurements, we build a proof-of-concept system to evaluate the feasibility of the system’s CIL control and test it with a spectrometer installed at the user’s viewpoint. The evaluation shows that the CIL at the user’s viewpoint can be kept below the threshold.