Optically Seamless Flexible Electronic Tiles for Ultra Large-Area Digital X-Ray Imaging

This paper presents a new flexible electronics assembly technique that combines individual digital X-ray detectors to create a much larger composite digital X-ray detector. The new assembly technique uses multiple flexible digital X-ray detectors manufactured on a thin, transparent, and flexible plastic substrate, which are overlapped to create the larger composite X-ray detector. The assembly technique, illustrated in a mechanical mockup, is optically seamless, and has the ability to scale up to extremely large X-ray imaging arrays. Feasibility and preliminary imaging performance were demonstrated by tiling several 16 × 16 pixel resolution prototype flexible X-ray detector test structures. Optical losses under typical digital radiography conditions were also measured by overlapping a plastic substrate flexible X-ray detector onto a commercial glass substrate digital X-ray imaging array. Approximately 5% signal loss was observed in the transparent plastic overlap region, and the seam edge imaging artifact was demonstrated to be correctable using commercial gain calibration. A key medical imaging application for this technology is single-exposure, low-dose, and full-body digital radiography.

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