8. Test patterns and reference documents

8.1 Test patterns

Test patterns are reference images used to qualify the image analyzer or analyzer + printer assembly. They are expensive, as they are produced using a photographic process (offset printing, which translates grays by screening, is not suitable).

To qualify black-and-white scanners, the test patterns feature gradations of gray, alternating white and black bars at various spacings (to measure resolution), centimeter scales (to check compliance with geometry), black lettering on white and gray backgrounds, white lettering on black and gray backgrounds (to assess the necessary contrast), text in several alphabets and of various sizes (to assess readability), continuous-tone photographs...

To qualify color analyzers, test...