The concept behind xray imaging has not changed in hundred years though technology has advanced- getting rid of the film and going digital, but their images still record the same kind of information: how a part of the patient's body absorbs the rays. MIT researchers are developing a new kind of x-ray imager that uses information that traditional machines ignore. By looking at how tissue refracts the rays, not simply at how it absorbs them. This change would increase the resolution of mammography, enabling doctors to detect smaller tumors earlier. A metal plate can filter radiation into coherent waves, making it possible to record refraction information for potentially higher resolution x-ray imaging.

Conventional x-ray tubes such as those used in mammography can't measure how a sample refracts waves unless the waves all start out going in the same direction at the same frequency, and x-rays can't be focused with lenses and mirrors. One way to achieve the uniformity, or coherence, necessary for refraction measurements is to run the x-rays through a particle accelerator. But these are too large and expensive for hospital use.
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