PURPOSE: To read out a character pattern on an object with high recognition accuracy even if the character pattern is inclined or shifted at its position by detecting the positional coordinates or two marks and operating these coordinates to nomalize the character pattern.
CONSTITUTION: The plane on which the characters 7d on the objects 4d, 4e on a belt conveyer 1, are drawn is parallel with the X-Y plane, the line direction of the character array 7d is parallel with the Z-X plane, but the plane on which characters 7e are drawn has an error angle ψ from the X-Y plane and the line direction of the character array 7e has an error angle θ from the X-Z plane. Assuming rectangles having prescribed relation to the characters 7d, 7e, the coordinates X, Y of other three points are calculated by specifying the left lower position of each rectangle as an origin. The X sinθ, Xcosθ cosψ are calculated to determine the coordinates of each point and normalize the character pattern. Consequently, the output of a photoelectric converter 5 is normalized by a processor 6 and is stored in an internal storage device to recognize the pattern.
MAEDA YOUJI
ENDOU TETSUO
SAITOU MITSUO
