411 REFERENCE · Wiktionary
Siemens star
Reference material by Wiktionary contributors. This retains its source identity and is not 411 news reporting.
English
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Etymology
Developed in the 1930s by Siemens & Halske AG to test the lenses of their narrow-film cameras.
Noun
A radial, sunburst-like test target used to measure the resolution and image quality of optical instruments, cameras, scanners, and printers.
en spoke target
en Printing Symbols
en eponyms