PROCESS OF DETECTION OF FLAWS ON SURFACE Russian patent published in 2001 - IPC

FIELD: instrumentation, detection of flaws of various origins on surface of tested objects. SUBSTANCE: light radiation is directed on to surface of moved tested object. Radiation zone of tested object is formed by way of crossing of light fluxes of directional radiation with area of normal projection of each of them larger than maximum projection of tested object from three identical sources as minimum arranged in space equidistantly one from another and from center of crossing of light fluxes. Tested object is moved uniformly and rectilinearly through radiation zone, light fluxes scattered by tested object are recorded by photodetectors with area of working surface equal to or larger than area of normal projection of light flux. Each photodetector is placed equidistantly from proper source in path of light flux. Recorded light fluxes are converted to discrete electric signals ( by level quantization, for example ), values of estimation of correlation moments between random values of signals on each pair of photodetectors are measured and series of values of estimation of correlation moments with number of terms in series determined by number of possible combinations of pairs of photodetectors is obtained in this manner. Arranging it by rise or by decrease one wins series of values of estimation of correlation moments rising or decreasing continuously. EFFECT: detection of flaws on surface of tested object in light flux without their any additional orientation with high authenticity, considerable reduction of time of flaw detection. 2 dwg, 1 tbl