MODEL MA0436-MA0647 PRECISION TEST PATTERNS

Precision Test Pattterns Model MA0436 Gammex MA 0437 Gammex MA 0438 Gammex MA 0439 Gammex MA0647 (not shown)            Precision test patterns provide an easy means of measuring the resolution and modulation transfer function of x-ray systems. They are compatible with all x-ray machines and are widely used by radiology equipment manufacturers. Resolution in lp/mm of a mammographic system is an objective means of monitoring image quality. The Mammographic Gold Line Pair Resolution Test Pattern Gammex MA0647 from Gammex provides 5 to 20 lp/mm resolution in 17 segments. The pattern is constructed of a gold-nickel alloy. This construction provides high contrast resolution patterns in the mammographic energy range. The wafer is equivalent to 25 microns of lead or 2.6 mm of aluminum at 20 KeV. Overall size is 10 mm by 25 mm. The resolution patterns all have specific applications. Group test patterns have varying numbers of line pair groups, with radiopaque numbers to indicate the resolution (in lp/mm) of each group.   Resolution Patterns                              A                B                   C                        D MA0436        0.5 to 5.0       16             0.10              110x40 MA0437        0.5 to 5.0        1             0.10               157x50 MA0438        0.6 to 5.0       20             0.01               50x50 MA0439        0.6 to 5.0       20             0.10               50x50 MA0647        5.0 to 20        17               *                 10x25 A = Range of Resolution in lp/mm B = Number of Groups or Sectors C = Lead Foil Thickness in m D = Dimensions in mm * = Gold nickel alloy equivalent to 25 microns of lead   SPECIFICATIONS   Gammex MA0436 0.5 to 5.0 lp/mm Sixteen Groups Size. . . . . . . . . . 110x40 mm (4.3x1.6 in) Weight. . . . . . . . 9 g (0.3 oz)   Gammex MA0437 0.5 to 5.0 lp/mm One Sector Size. . . . . . . . . . 157x50 mm (6.2x1.9 in) Weight. . . . . . . . 9 g (0.3 oz)       Gammex MA0438 and Gammex MA0439 0.6 to 5.0 lp/mm Twenty Groups Size: . . . . . . . . . 50x50 mm (1.9x1.9 in) Weight: . . . . . . . 9 g (0.3 oz)   Gammex MA0647 (not shown) 5 to 20 lp/mm Seventeen Segments Size: . . . . . . . . . 10x25 mm (4x10 in) Weight: . . . . . . . 3 g (1 oz)