Method of and apparatus for optically checking the appearances of

Abstract

A method of optically checking the appearances of chips and sorting the chips comprises the steps of feeding chips onto chip-passage body to cause the chips to run on the chip-passage body in a predetermined direction; during the running of the chips on the chip-passage body, individually separating the chips to stop the chips one by one at each of two predetermined checking positions; irradiating light obliquely and straightly with respect to a chip at one of the predetermined checking positions to pick up an optical image of one of undersurface and top surface sides of the chip as a video signal by means of a first TV camera; irradiating light obliquely and straightly with respect to the chip at the other of the predetermined checking positions to pick up an optical image of the other of the undersurface and top surface sides of the chip as a video signal by means of a second TV camera; sending the video signals to image processing sections, each of which includes at least an analog-to-digital conversion unit, a video memory and a central processing unit, to process the video signals in the image processing sections and obtain data on the appearance of the chip and a tilt angle of the chip on each of the predetermined checking positions of the chip-passage body, thereby checking on the basis of the data whether the chip is acceptable or defective in its appearance; and thereafter sorting chips on the basis of the check results. Also, an apparatus for optically checking the appearances of chips and sorting the chips is disclosed.