title: An x-ray milliprobe analyser with photographic recording of the spatial distribution of elements.
abstract: An X-ray milliprobe analyser has been built and its performance and usefulness evaluated. The instrument consists of a fluorescent X-ray spectrometer in which the primary X-ray beam from the sealed-off tube is collimated so that only a small area on the specimen, 0.3 or 1 mm in diameter, is irradiated. The large loss in intensity of the fluorescent X-rays is offset to some extent by the use of a focussing curved-crystal analyser. The usefulness of the instrument has been greatly increased by the incorporation of an automatic raster scanning motion in the sample holder, and of a similar motion in a colour-film holder which moves across a light beam. The colour of this beam is altered according to the measured concentration of the element, so that a coloured mosaic picture of its distribution is built up. The limits of detection of a wide range of elements are in the range 200-2000 ppm for the rather short counting period of 10 sec per point which is necessary when scanning a large area.
authors.affiliation: Analytical Sciences Division, Atomic Energy Research Establishment Harwell, Berks., U.K.
authors.forename: J T
authors.initials: JT
authors.lastname: Campbell
authors.forename: F W
authors.initials: FW
authors.lastname: Garton
authors.forename: J D
authors.initials: JD
authors.lastname: Wilson