A low-absorption x-ray energy filter for small-scale applications
2009 (English)In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 17, no 14, 11388-11398 p.Article in journal (Refereed) Published
We present an experimental and theoretical evaluation of an x-ray energy filter based on the chromatic properties of a prism-array lens (PAL). It is intended for small-scale applications such as medical imaging. The PAL approximates a Fresnel lens and allows for high efficiency compared to filters based on ordinary refractive lenses, however at the cost of a lower energy resolution. Geometrical optics was found to provide a good approximation for the performance of a flawless lens, but a field-propagation model was used for quantitative predictions. The model predicted a 0.29 Delta E/E energy resolution and an intensity gain of 6.5 for a silicon PAL at 23.5 keV. Measurements with an x-ray tube showed good agreement with the model in energy resolution and peak energy, but a blurred focal line contributed to a 29% gain reduction. We believe the blurring to be caused mainly by lens imperfections, in particular at the periphery of the lens. (C) 2009 Optical Society of America
Place, publisher, year, edition, pages
2009. Vol. 17, no 14, 11388-11398 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-128378ISI: 000267761200018OAI: oai:DiVA.org:uu-128378DiVA: diva2:331463