The USAF-Chart (also: USAF Resolution Test Chart , USAF 1951 Resolving Power Test Target ) was designed in 1951 by the USAF , i.e. the air forces of the United States of America , to measure the resolution of to be able to check optical instruments, in particular aerial cameras , using a test image that is easy to interpret .
Despite its great age, this test chart is still used in a variety of ways today. It can be obtained in different sizes from specialist retailers and consists of groups of vertical and horizontal stripes with different widths and spacing. The arrangement is based on the then valid military standard MIL-STD-150A. Test boards of this type are used to determine the resolution of optical devices such as cameras or scanners or to adjust them optimally. The group of stripes in which the individual stripes can no longer be seen separately indicates the resolution limit of the optical device to be tested.