A scintillator is a material that transforms high energy radiation like x-rays into visible light. This light can then easily be detected by inexpensive devices like CCD or CMOS cameras. In medical applications, x-rays are used, because they partly penetrate the human body, with different absorption by dense tissue like bones or tumors. Scintillator plates then transform the transmitted radiation into visible light, which can be amplified and captured by an image sensor. The thicker the plate, the more visible light can be created.

Unfortunately, there is a major issue with conventional scintillator plates: The created light spreads while it travels through the scintillator, which leads to a light cone rather than a light spot. Thus, a camera chip would register a signal on several pixels for each incident x-ray.

The amount of absorbed x-rays and therefore the signal strength depends on the material thickness. Therefore, conventional scintillator plates always involve a tradeoff between sensitivity and resolution.