The Philips circle pattern (also referred to as the Philips pattern or PTV Circle pattern) refers to a family of related electronically generated complex television station colour test cards. The content and layout of the original colour circle pattern was designed by Danish engineer Finn Hendil (1939–2011) in the Philips TV & Test Equipment laboratory in Amager (moved to Brøndby Municipality in 1989) near Copenhagen under supervision of chief engineer Erik Helmer Nielsen in 1966–67, largely building on their previous work with the monochrome PM5540 pattern. The first piece of equipment, the PM5544 colour pattern generator, which generates the pattern, was made by Finn Hendil and his group in 1968–69. The same team would also develop the Spanish TVE colour test card in 1973.
Since the widespread introduction of the original PM5544 from the early-1970s, the Philips Pattern has become one of the most commonly used test cards, with only the SMPTE and EBU colour bars as well as the BBC's Test Card F coming close to its usage.
The Philips circle pattern was later incorporated into other test pattern generators from Philips itself, as well as test pattern generators from various other manufacturers. Equipment from Philips and succeeding companies which generate the circle pattern are the PM5544, PM5534, PM5535, PM5644, PT5210, PT5230 and PT5300. Other related (non circle pattern) test card generators by Philips are the PM5400 (TV serviceman) family, PM5515/16/18, PM5519, PM5520 (monochrome), PM5522 (PAL), PM5540 (monochrome), PM5547, PM5552 and PM5631.

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