Radiation detector

Abstract

There is provided a radiation detector that appropriately corrects an offset within a minute read cell without increasing area while achieving high-speed measurement at a high counting rate. A radiation detectorhaving a plurality of single-photon-counting imaging cells includes, for each imaging cell, a photodiodewhich is applied with a reverse bias voltage and generates a current signal in response to incidence of radiation, a previous-stage DA converter dconfigured to correct an input signal based on the current signal generated by the photodiode, an amplifier kconfigured to amplify the signal corrected by the previous-stage DA converter d, a subsequent-stage DA converter dconfigured to correct a charge signal amplified by the amplifier k, a wave height discriminatorconfigured to discriminate output signals based on the signal corrected by the subsequent-stage DA converter d, and a counterconfigured to count the discriminated signals.