1. An X-ray imaging apparatus comprising: an X-ray generator configured to emit X-rays to a subject; an X-ray detection panel comprising: a plurality of light receiving elements each configured to receive X-rays that have passed through the subject, convert the X-rays into an electric signal, and output the electric signal; and a plurality of capacitor modules respectively corresponding to the plurality of light receiving elements, each of the plurality of capacitor modules comprising a plurality of capacitors connected to a corresponding one of the light receiving elements and configured to store the electric signal output from the corresponding light receiving element in at least one capacitor of the plurality of capacitors; and an image processor configured to read out the electric signal stored in the at least one capacitor of each of the plurality of capacitor modules to generate at least one X-ray image.