Abstract: Among other things, one or more systems and/or techniques for calibrating a direct conversion detector array are provided. An electrical charge is generated on an interface of a photoconductor (e.g., amorphous selenium) of the detector array when there is a change in voltage that is applied to the photoconductor. Such a change in voltage may occur because the voltage that is supplied to the photoconductor by a power supply is changed. The changed voltage causes an electrical charge to be produced, or causes a change in the net charge density at an interface of the photoconductor, that is substantially similar to the electrical charge that may be produced when radiation impinges the detector array. In this way, calibrations of the detector array (e.g., the generation of a uniformity map, defect table, etc.) may be performed without the emission of radiation and onsite or outside of a factory setting.