According to image system OEM’s, “Image is everything”, or “Seeing is believing”. A list of great specifications is not as important as the end results. There are several recognized standards for measuring focal spot size, each of which deviate significantly. Some X-ray tube manufactures specify a small spot, yet the image can be blurry due to oblong or double (dog bone) focal spots. We produce X-ray tubes with small, round focal spots, minimizing un-sharpness, for clearer images.

The current standards for focal spot measurement (EN 12543 and ASTM E 1165, IEC 60336:) describe different measurement methods, which do not provide identical values. Sufficient image quality depends on the inherent detector unsharpness and the geometric unsharpness. The geometric unsharpness is determined by the focal spot intensity distribution and the magnification used.

Therefore, the shape of the focal spot cannot be neglected, even if the shape distribution is not required by any standard practice.

Instrumentation can be enhanced by x-ray optics. Even small focal spot x-ray tubes can produce spot sizes ranging in diameter from as small as several hundred micrometers to as large as several millimeters. X-rays are collected from a divergent source, which then directs them to a small focused beam on the surface. This beam can be as little as tens of micrometers. Small focal spot x-ray tubes deliver and enhance spatial resolution. This improves the performance when analyzing small features.

Why We are Better…
Consequently, we don’t rely on focal spot standards to establish image quality – we let the image quality speak for itself.

Related Products:

Micro X-Ray Integrated Micro Focus Tube and Power Supply

Micro Focus X-Ray Tube with Integrated Power Supply
With focal spot as small as 5 microns and up to 110kV, these tubes are perfectly suited for small feature imaging applications.

Micro X-Ray Mini Focus Packaged X-Ray Tube

Mini Focus, Packaged X-Ray Tubes
These X-Ray tubes are fully shielded and provide excellent thermal properties that enable continuous operation without compromise


We are always happy to help or advise on your specific x-ray requirements—from general to technical questions we are happy to help.