04759072 is referenced by 34 patents and cites 8 patents.

In detecting surface defects of a hot metal body, e.g. hot-rolled steel sheet, by using a first video signal derived from radiation spontaneously radiated from a target area of the hot metal surface and a second video signal derived from external light projected on and reflected from the same target area of the hot metal surface, the rate of false detection by the influence of noise signals attributed to metal oxide present on the hot metal surface is greatly reduced by converting the first and second video signals respectively into first and second binary signals, synchronously feeding the first and second binary signals to an AND circuit and detecting the locations of such defects based on the output of the AND circuit. Preferably near-infrared region of the radiation is used in producing the first video signal and visible light as the external light.

Title
Method and apparatus for detection of surface defects of hot metal body
Application Number
684243
Publication Number
4759072
Application Date
May 6, 1987
Publication Date
July 19, 1988
Inventor
Hideyuki Hanafusa
Takamatsu
JP
Hirosato Yamane
Kurashiki
JP
Agent
Austin R Miller
Assignee
Futec Incorporated
JP
Kawasaki Steel
JP
IPC
G06K 9/00
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