Since imaging systems are often classified in terms of resolution and contrast, our photograhic paper targets allow users to evaluate their systems using the standard USAF format for resolution measurements at different contrast levels. For example, they are useful when lens designers develop lens systems to provide high contrast at low resolution, but neglect contrast at higher resolutions. They prove handy when two lens designs have the same limiting resolution, but drastically different contrast performance at lower resolutions. By imaging targets of various contrast, the user can make qualitative comparisons between lenses as well as evaluate the performance of the system for objects with varying or low contrast levels.
|Number of Line Pairs / mm in USAF Resolving Power Test Target 1951|