Several factors influence the choice of anode and focus.
The primary considerations include the use of the tube, whether for powder diffractometry or single work, together with the minimisation of the background radiation. The selection then depends on factor such as the sample penetration required, the d-value range under study and possible problems with fluorescence of the sample. For most diffractometry applications, both high resolution and high intensity are desirable. Here, a long fine focus tube offers great advantages, combining the resolution of a fine focus tube with much of the intensity of a broad focus tube. The degree of collimation normally employed in camera work demands a high intensity source, such as is provided by a fine focus tube.
Normal focus tubes offer a compromise between intensity and line resolution, for example they can be employed to advantage when both a point-focus camera and a diffractometer are to be mounted on a single tube shield. In quantitative X-ray diffractometry the degree of collimation is comparatively minor, while the sample is usually large. If intensity is the only major requirement then a broad focus tube is preferred.
In addition to the standard range, special anode materials may be specified. Sc, Ti, V, Mn and Ni targets are available to order.
Recently special Mo/W double anode X-ray tubes, with a long fine focus and a maximum rating of 2200 Watts have been developed.

The high power ceramic X-ray tubes offers a number of outstanding features and benefits including:

• High efficiency and longer lifespan. The high efficiency design has led to enhanced cathode conductivity while, at the same time, efficient anode cooling ensures that tube lifespans are increased substantially.
• Higher spectral purity. Excellent spectral purity and precise beam focusing are provided by an advanced ceramic cathode design.
• Great choice of anode materials. A wide range of anode materials is available on request, further increasing the range of analytical performance.
• Advanced technology improves performance. The anode body, in combination with ceramic based insulation, provides a tube with a superior performance.