Universal mask for hard X rays

TL;DR

This paper demonstrates a novel method called ghost projection for flexible patterning of hard X-ray beams, enabling dynamic beam shaping and potential applications in lithography and other particle fields.

Contribution

It introduces the concept of ghost projection for hard X rays, providing a proof-of-concept and discussing its potential for universal, on-demand patterning and beam shaping.

Findings

Experimental proof-of-concept for hard X-ray ghost projection

Pattern flexibility up to a tunable constant offset

Potential for universal lithographic masks and beam-shaping devices

Abstract

The penetrating power of X rays underpins important applications such as medical radiography. However, this same attribute makes it challenging to achieve flexible on-demand patterning of X-ray beams. One possible path to this goal is ``ghost projection'', a method which may be viewed as a reversed form of classical ghost imaging. This technique employs multiple exposures, of a single illuminated non-configurable mask that is transversely displaced to a number of specified positions, to create any desired pattern. An experimental proof-of-concept is given for this idea, using hard X rays. The written pattern is arbitrary, up to a tunable constant offset, and its spatial resolution is limited by both (i) the finest features present in the illuminated mask and (ii) inaccuracies in mask positioning and mask exposure time. In principle, the method could be used to make a universal lithographic mask in the hard-X-ray regime. Ghost projection might also be used as a dynamically-configurable beam-shaping element, namely the hard-X-ray equivalent of a spatial light modulator. The underpinning principle can be applied to gamma rays, neutrons, electrons, muons, and atomic beams. Our flexible approach to beam shaping gives a potentially useful means to manipulate such fields.