In micrographics, it is the product of the number of the pattern resolved in the ISO Test Chart No. 2 multiplied by the reduction and is expressed in line pairs per millimeter. Consists of an arrangement of test patterns of increasing spatial frequency expressed in line pairs per millimeter containing patterns numbered from 1.0 to 18. Made up of two sets of five parallel line rectangular groups that are perpendicular to each other. A pattern is resolved when the two groups of lines constituting this pattern can be visually distinguished in both directions. Instruments Microscope with a magnification between 0.5 and 1.0 times the anticipated resolving power of the system expressed in line pairs per millimeter.
Procedure View the test chart at the appropriate magnification.
Determine from the test chart the pattern number associated with the smallest test pattern that can be resolved. Use the test chart with the lowest pattern number to determine the defect classification if a frame contains more than one test chart. Assess a defect in accordance with the Defect Classification Table. The test target is composed of five ISO Test Charts No. 2. The center test chart resolved the 5.0 pattern while the other four test charts resolved the 6.3 pattern.