Abstract: The present disclosure pertains to a light sensing system configured to determine an amount of ambient light exposure experienced by a subject. The present invention wirelessly exchanges light information between different wearable devices of the same user and/or between devices of different users. Local and/or central light profile databases are built-up by the system and are shared between the devices so that light data that is typical for a location at a specific time of day and year can be used to estimate current ambient light levels for situations in which no measurement can be taken.

Abstract: The present invention relates to a light sensing system for sensing ambient light intensity, comprising a light sensing device with at least one light sensor and a calibration device for calibrating the sensor. The calibration device comprises at least one light source that emits light with a standard intensity. The invention is further related to a corresponding method for calibrating a light sensing device, comprising the illumination of the light sensor of the light sensing device with light that has a standard intensity, the comparison of the output intensity signal of the sensor with an expected signal that corresponds to the standard intensity, and the matching of the output intensity signal of the sensor to the expected signal by adjusting a gain parameter of the sensor.

Abstract: The present disclosure pertains to a light sensing system configured to determine an amount of ambient light exposure experienced by a subject. The present invention wirelessly exchanges light information between different wearable devices of the same user and/or between devices of different users. Local and/or central light profile databases are built-up by the system and are shared between the devices so that light data that is typical for a location at a specific time of day and year can be used to estimate current ambient light levels for situations in which no measurement can be taken.

Abstract: The present invention relates to a light sensing system for sensing ambient light intensity, comprising a light sensing device with at least one light sensor and a calibration device for calibrating the sensor. The calibration device comprises at least one light source that emits light with a standard intensity. The invention is further related to a corresponding method for calibrating a light sensing device, comprising the illumination of the light sensor of the light sensing device with light that has a standard intensity, the comparison of the output intensity signal of the sensor with an expected signal that corresponds to the standard intensity, and the matching of the output intensity signal of the sensor to the expected signal by adjusting a gain parameter of the sensor.

Abstract: Information about a person's circadian rhythm is generated in terms of a difference between a reference and a specific circadian time for a specific wall-clock time or in terms of a difference between a special and a specific wall-clock time for a specific circadian time event.