Star Patterns

Star-Ray Test Patterns for Measuring Focal Size Star X-Ray Test Patterns for Measuring Focal Spot Size Focal spot size can be determined by observing the regions of blurring which occur when the pattern is Radio graphed by an x-ray source of finite dimensions. Radiation from different areas of the focal spot will cause a periodic blurring of the pattern due to penumbra effects. Knowledge of the geometric factors, and the distance from the center of the pattern to the region where blurring occurs, will permit the calculation of the focal spot size with the same accuracy as measurements made with a pinhole camera.

Item 293637 - 07-509-2000
High-Precision Star X-Ray Test Pattern, 55 mm Ø; For measuring focal spots from 1 mm and up. Has four 45° sectors with a 2° angle of a single line within a sector. Lead-foil thickness: 0.05 mm

Item 293641 - 07-543-2000
High-Precision Star X-Ray Test Pattern, 55 mm Ø. For measuring focal spots from 0.8 to 1.5 mm. Has four 35° patterned sections with a 1.5° angle of a single line within a sector. Lead-foil thickness 0.03 mm

Item 293638 - 07-510-2000
High-Precision Star X-Ray Test Pattern, 55 mm Ø. For measuring focal spots from 1 mm and up. Has one 360° pattern sector with a 2° angle of a single line within a sector. Lead-foil thickness 0.05 mm