Measuring radioactivity has a long history and innumerable academic and commercial applications in nuclear safety, defense, medicine, biology, material sciences, etc. That may soon change, now anyone can start their own virtual lab and explore nuclear science with a $20 webcam.
It’s more than just radiation detection with devices like Geiger counters, the software capabilities can classify the type of radiation and can differentiate between various kinds of radioactive materials. They track the real-time dark noise statistics to find the right threshold. Then, there is an analyzing step when the particle energies are estimated, all software-based and done in real time.
The webcam sensor is shielded from visible light by aluminum foil and uses a special software package to analyze the video stream for characteristic patterns.
Beta particles can be measured with high precision (error < 5%) but the relative hit rate depends on the material of the measurement sample – this indicates that the sensor’s sensitivity varies with the particles’ energy. It is however unable to detect neutrons even from strong sources, and further work would be needed to do so, such as submersion in helium gas.
Source: Vienna University of Technology