High contrast, CdTe portal scanner for radiation therapy

A solid state, CdTe, linear array, portal imaging system is presented. One of the most promising new technologies for improving the quality of radiation therapy is the use of real-time systems to produce portal images. In the approach presented, a linear array of 256 CdTe photovoltaic detectors attached to a very compact linear scanner, all of which will be mounted in a cassette shaped package to be located under the patient table, is constructed. The high stopping power of the CdTe allows a high contrast image to be made using only a single linac pulse per line, resulting in a high contrast image in under 5 s