The method of measuring the height and height measuring device

A highly measuring device (100), wherein the image forming optical system (20) is moved relative to the focal position of the measurement object (10) relative to the optical axis direction; scanning is performed; sequentially obtained by the image forming optical system (20) is formed (10) an image of the measurement object; and obtaining an image focus position of each pixel, thereby obtaining a measurement object corresponding to the pixel (10) at a position relative to the height value; wherein for a plurality of images obtained by scanning pixels , fit to a first function based on a numeric sequence of coordinate values ​​and light intensity values ​​or coordinate values ​​on the optical axis comprises performing numerical processing and obtained by the light intensity value (f) defining a second function (G); and the value of relative height value of the position on the optical axis when used as a correlation value between the sequence and the second function (g) becomes the maximum or minimum measurement object corresponding to the pixel at the position.