In cases of nuclear disasters it is desirable to know one's personal exposure to radioactivity and the related health risk.
Usually, Geiger-Mueller tubes are used to assess the situation. Equipping everyone with such a device in a short period
of time is very expensive. We propose a method to detect ionizing radiation using the integrated camera of a mobile
consumer device, e.g., a cell phone. In emergency cases, millions of existing mobile devices could then be used to
monitor the exposure of its owners. In combination with internet access and GPS, measured data can be collected by a
central server to get an overview of the situation.
During a measurement, the CMOS sensor of a mobile device is shielded from surrounding light by an attachment in front
of the lens or an internal shutter. The high-energy radiation produces free electrons on the sensor chip resulting in an
image signal. By image analysis by means of the mobile device, signal components due to incident ionizing radiation are
separated from the sensor noise. With radioactive sources present significant increases in detected pixels can be seen.
Furthermore, the cell phone application can make a preliminary estimate on the collected dose of an individual and the
associated health risks.