Abstract: A goniometer in an X-ray diffraction device comprises a sample table rotatably provided about a center axis of a sample for holding a sample, an X-ray source rotatably provided about the center axis of the sample for irrdiating first X-ray onto a sample, and an X-ray detector rotatably provided about the center axis of the sample for detecting second X-rays resulting from the irradiation of the first X-rays, the second X-rays being diffracted X-rays depending upon a sample. The sample table, the X-ray source an the X-ray detector are rotatable independently of one another, and a component to be fixed can be freely selected in accordance with a purpose of measurement and sample attachments employed. As such, various kinds of measuring methods are available to perform X-ray diffraction analysis by a single goniometer.

Abstract: An X-ray is generated when thermoelectrons emitted from a cathode impinge upon an anode, and the X-ray thus generated is taken out from a window. The cathode has a surface formed with two grooves intersecting at a right angle with each other and two coil filaments are fitted thereinto. By selectively heating one of the two coil filaments, a region on the anode upon which the thermoelectrons impinge is changed, whereby one of point- and line-focusing X-rays is selectively taken out from the window provided at a portion slightly below the face of the anode and at a wall of a casing of an X-ray tube.