Patent ID: 6570651
Filing Date: 2003-05-27
Classification: G01N

Abstract:
A method of determining the optical quality of and detecting faults in transparent material (2) wherein a video camera (1) is arranged to monitor the emitted light of an illuminating device (3) that either is transmitted through or is reflected by the transparent material (2), the focus being on the transparent material (2), and the video camera (1) generates signals in dependence on the quality of the transparent material (2) and these signals are evaluated, characterized byusing at least one illuminating device (3) for creating a pattern (4) of adjacent partial portions (5a, 5b) alternately different at least in color and/or in intensity, picking up the pattern (4) in a field of view of the video camera (1), generating a first video signal U1 caused by the light transmitted through a first partial portion (5a, 5b) of the pattern (4) and generating a second video signal U2 caused by light transmitted through the second partial pattern (5b, 5a) of the pattern (4), and evaluating the quality of the transparent material (2) by utilizing a change of the intensity of the video signals U1, U2.