A method of designing an x-ray emitter panel 100 including the step of determining a pitch scale, r, to be used in placing x-ray emitter elements 110 on the panel 100, thereby arriving at a specific design of x-ray emitter panel 100 suitable for a specific use. The pitch scale is determined by solving an inequality which depends on, inter alia, the maximum separation D between the emitter panel and a detector panel 130, the surface area of the emitter panel, the density of detectors in the detector panel, the minimum number of photons required to arrive at an individual detector to obtain a viable image, and a predetermined absorption factor due to tissue 120 placed between the emitter and detector panels.
