focal spot size

fo·cal spot size

(fō'kăl spot sīz),
The measured size of a focal spot of an x-ray tube, a function of the actual size of the cathode and the angulation of the anode surface. See: focal spot.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
One option available to cutting machine builders is to use a more capable cutting head with a motorised zoom collimator and variable beam expander, which enables the focal spot size to be modified.
Schematic indicating the effect on the focus of an x-ray tube as the focal spot size increases.
Spatial resolution in CT is primarily determined by the pixel size of the detector, the ratio of the distance between the source and the object and the object and the detector (geometric magnification), and the X-ray focal spot size (Goldman 2007; Romans 2011; Staude & Goebbels 2011).
Besides the physical dimension of the detector, the focal spot size of the lens mechanism is another factor that can cause signal fall-off.
Measuring the acoustic impedance with a 230-MHz transducer would be time-consuming and have a more localized reading, however, because the focal spot size of the transducer is so much smaller.
The different geometries have been compared in terms of the focal spot size, the side lobe level, and the amplitude of the field at the focal point.
Laser fluence used is 3.18 J/cm2 where the focal spot size on target surface is 100 um.
Knowing the focal spot size and position during the critical start-up phase of a manufacturing process is critical to providing consistent and quality parts.
The phantom was imaged at 40 kV using the small focal spot size. The images were scored on the 3 megapixel screen used for clinical evaluation.
The penetration depth in laser welding is proportional to the power density of the laser beam and is incident function between the focal spot size and its power.

Full browser ?