ABSTRACT
This chapter discusses the concept of single photon processing hybrid pixel detectors before moving on to characterize hybrid pixel detectors using synchrotron radiation and in particular monoenergetic pencil beams. The beams produced by synchrotrons are generally very clean and have excellent energy resolution. A monochromatic pencil beam is a very useful tool for detector characterization since both the position and the amount of energy deposited are then known. The Timepix chip is a hybrid pixel detector developed in the framework of the Medipix2 collaboration. While Timepix is a general-purpose chip, the Medipix3RX is much more aimed at x-ray imaging. Depending on the chip, two types of energy calibration are necessary: calibration of the analog threshold and calibration of the time over threshold response. By applying a threshold and counting each photon, the noise from integrating the leakage current seen in charge-integrating devices is removed.
