The compound refractive x-ray lenses (CRLs) are used to focus and collimate hard x rays, and image objects using hard x rays. The lenses have been experimentally shown to operate in energy ranges from 4 to 80 keV, at focal lengths as small as 5 cm, with numerical apertures of 10-3 or better. These operational ranges can be further extended.
The main principle behind compound refractive lenses (CRLs) is an ability of a group of thin lenses to greatly shorten the focal length. A series of N lenses with small apertures is used to achieve both one- and two-dimensional focusing and imaging at x-ray photon energies, where refractive imaging has previously been thought to be impossible due to the weak refraction of x rays. Note that the refractive index for x-rays is less than 1.
Therefore, unlike visible light optics which will cause visible rays to diverge, the concave lens will focus x-ray photons. Among the lenses we offer are cylindrical, spherical and 1- and 2- dimensional parabolic units.
From Adelphi Technology Inc.