Dimension and shape measurements with high accuracy using composite image sensors

A new composite image sensor system is proposed. Two different type image sensors, area and line sensors, are used effectively to make dimension and shape measurements with high accuracy. An area sensor is used to obtain a whole image of the object at an accuracy of 1 mm and to pick up regions which are necessary to measure shapes and position of edges or holes, then a line sensor is used to obtain a high resolution image of picked-up regions by rotating and scanning the line sensor at an accuracy of 0.1 mm. This sensor system has an advantage that the acquisition time of image input is shortened and that the amount of data is much reduced as compared with an image input system using a line sensor only.Experimental results show that this composite image sensor system is available in the field of not only parts'dimension and shape measurement but also three-dimensional geometrical measurement.