1. A radiation projection detector for generating signals in response to a radiation beam, the detector comprising a first imager, the first imager having: a conversion layer configured to generate light photons in response to a radiation; a photo detector array aligned with the conversion panel, the photo detector array comprises a plurality of lines of detector elements, each of the detector elements configured to generate a signal in response to the light photons received from the conversion layer; and an access circuit coupled to the photo detector array and configured to collect signals from two or more of the lines of detector elements simultaneously.