PERPENDICULARITY MEASURING METHOD AND AN APPARATUS THEREOF

A non-contacting type method for measuring perpendicularity of a straight post installed perpendicularly to a reference plane is performed by picking up partial images of an upper end and a lower end of the post in two directions vertical to each other to combine obtained images into one image, calculating inclinations or deviations of four images of lower end portion and upper end portion in the combined image, and comparing the inclinations or deviations to measure the perpendicularity with respect to the reference plane. An apparatus thereof includes a measuring section for optically obtaining image data of the object to be measured, a measuring-part driving unit for driving the measuring part in the X, Y and Z directions which are perpendicular to one another, and a data processing part for processing and calculate the image data obtained by the measuring part to display the result of perpendicularity calculation. Thus, by adopting an optical principle without actually contacting the measured object, a problem of causing an error due to the direct contact is solved while being applied to the measurement of an object with a small measuring space. Because a measuring section is freely moved with respect to the X, Y and Z directions to execute the measurement, even a different object requires no separate setting to thus facilitate the measuring.