SEAL IMAGE COLLATING DEVICE

PURPOSE:To improve the detecting accuracy and at the same time to shorten the time required for decision of coincidence, by recognizing the external form of a registered seal image pattern and using an optimum tilt angle detecting method in response to said external form of the pattern to detect the tilt angle and position of the seal image pattern. CONSTITUTION:The center point coordinate and the tilt angle of a seal image pattern to be collated are detected by a position detector part 3 and a tilt angle detecting part 40 respectively. On the other hand, the center point coordinate and the tilt angle of a registered seal image pattern 5 re detected by a position detecting part 6 and a tilt angle detecting part 70 respectively. In response to the result of this detection, the position is matched by a position matching part 8 for the pattern 2. Then the coincidence or discordance is decided at a coincidence deciding part 9 for both seal image patterns. The external form of the pattern 5 is discriminated by an external form discriminating part 100. The result of this discrimination is given to the detecting parts 40 and 70 respectively. Both parts 40 and 70 detect tilt angles with an optimum tilt angle detecting method in reponse to the external form of the pattern 5.