UCL Events


Detecting the undetectable - transforming the use of x-rays 124 years after their discovery

29 October 2019, 1:00 pm–2:00 pm

Conventional and phase-contrast x-ray of an insect

This lecture raises awareness of World Radiography Day on 8 November. The date marks the anniversary of the discovery of x-radiation by Wilhelm Roentgen in 1895. November 8 2019 marks 124 years since the discovery of the x-ray.

This event is free.

Event Information

Open to







Emma Hart


Darwin Lecture Theatre
044: Darwin Building
Gower Street
United Kingdom

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About the lecture:

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).

About the Speaker

Sandro Olivo

Professor of Applied Physics at Department of Medical Physics and Bioengineering, UCL

Sandro is Professor of Applied Physics with the Department of Medical Physics and Bioengineering, and the spokesperson of the "Advanced X-Ray Imaging" (AXIm) Group. Sandro has worked in x-ray imaging for 25 years, and is considered a pioneer in the field of X-ray phase contrast imaging, having co-designed the in vivo mammography system operational at the Trieste synchrotron, and invented the “edge-illumination” and “coded-aperture” methods, currently being translated in a number of application fields by Nikon and other companies.

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