| 摘要 |
In one embodiment, an x-ray neutron instrument includes an x-ray or neutron lens (10) disposed in a path for x-rays or neutrons in the instrument. The lens (10) comprises multiple elongate open-ended channels (12) arranged across the path to receive and pass segments of an x-ray or neutron beam (14). The channels (12) have side walls reflective to x-rays or neutrons of the beam incident at a grazing angle less than the critical grazing angle for total external reflection of the x-rays or neutrons, whereby to cause substantial focusing or collimation and/or concentration of the thus reflected x-rays or neutrons. In a different embodiment, a condensing-collimating channel-cut monochromator comprises a channel (22) in a perfect-crystal or near perfect-crystal body (20). This channel (22) is formed with lateral surfaces (24, 26) which multiply reflect, by Bragg diffraction from selected Bragg planes, an incident beam (28) which has been collimated at least to some extent. The lateral surfaces (24, 26) are at a finite angle to each other whereby to monochromatize and spatially condense the beam (28) as it is multiply reflected, without substantial loss of reflectivity or transmitted power. |
