Lunch Hour Lecture: Detecting the Undetectable - Transforming X-rays 124 Years After Their Discovery

Most people are familiar with the medical use of x-rays, however they are used much more widely, e.g. in industrial testing, materials science, biology, security inspections, cultural heritage preservation. This notwithstanding, x-ray imaging has been performed in the same way since Roentgen’s discovery more than 120 years ago: by exploiting differences in x-ray attenuation. While this approach is often reliable, it breaks down when thin details need to be detected, or materials with similar attenuation distinguished (e.g. tumours in soft tissue). We have developed a solution based on fact that the x-ray speed changes when different materials are traversed ("phase" contrast).