A parabolic primary mirror that directs the X rays toward an elliptical secondary mirror, which bounces the X rays out of the incoming light path to a detector.
A single large slab of material that totally absorbs the individual X rays that encounter it.
Special lenses made of fluorite and/or other minerals that transmit X rays efficiently.
A spherical primary mirror that directs the X rays toward a specially shaped secondary mirror, which bounces the X rays back down through a hole in the primary mirror to a detector.
A series of concentric, tapered, tubular mirrors that the X rays strike at shallow grazing incidence angles.