High-resolution detector having a reduced number of pixels

A phase-contrast imaging detector includes a plurality of pixels. Each pixel includes a detection material that generates a measurable parameter in response to X-ray photons. Each pixel also includes a plurality of sub-pixel resolution readout structures. The sub-pixel resolution readout structures are in an alternating pattern with a spacing therebetween that is larger than a frequency of a phase-contrast interference pattern but small enough to enable charge sharing between adjacent sub-pixel resolution readout structures when an X-ray photon hits between the adjacent sub-pixel resolution readout structures. The phase-contrast imaging detector also includes readout circuitry configured to read out signals from the plurality of sub-pixel readout structures. The plurality of sub-pixel resolution readout structures includes two or more electrodes having alternating arms that form an interleaved comb structure.