1. A method for detecting an image of an object, comprising: transmitting an x-ray beam through the object and emitting from the object a transmitted beam; directing the transmitted beam at an angle of incidence upon a crystal analyzer; detecting a first image of the object from a first diffracted beam emitted from the crystal analyzer positioned at a first angular position; detecting a second image of the object from a second diffracted beam emitted from the crystal analyzer positioned at a second angular position; combining the first image and the second image to derive a refraction image; and deriving a mass density image of the object from the refraction image.