Simple method for focusing x rays using tapered capillaries

Edward A. Stern, Zwi Kalman, Aaron Lewis, Klony Lieberman

Research output: Contribution to journalArticlepeer-review

84 Scopus citations


A new method of focusing x rays is described using appropriately tapered capillaries. The x rays are incident on the inner surface of the capillary below the critical glancing angle and reflect due to total external reflection. By appropriately narrowing the capillary, the x rays can thus be focused in a broad band of energies. The theory of the effect and optimum taper is described. A measurement verifying the focusing capability of the method is presented. The method appears practical for focusing bending magnet synchrotron radiation around 8 keV down to a diameter of 10 μm from an initial dimension of 1-mm 2 incident cross section with an attenuation of the total energy of ∼2, i.e., an increase in the intensity per unit area of 6.5 X 103. Greater focusing is possible with softer x rays and from undulator sources. The wide-ranging applicability of the technique is discussed.

Original languageEnglish
Pages (from-to)5135-5139
Number of pages5
JournalApplied Optics
Issue number24
StatePublished - 15 Dec 1988
Externally publishedYes


Dive into the research topics of 'Simple method for focusing x rays using tapered capillaries'. Together they form a unique fingerprint.

Cite this