Method and apparatus for detecting surface defects on a band travelling at high speed

摘要

This apparatus comprises a device for illuminating in a permanent manner a zone in which the band travels, a television camera having a high luminous sensitivity and a low remanence controlled for exposure during constant periods of time which are short relative to the speed of travel of the band with a frequency of recurrence which is substantially equal to the speed of the band divided by the length of said zone in the direction of travel of the band. In this way, said successive images detected constitute a substantially continuous representation of the band. An electronic circuit is provided for analysing the images received by the camera.