Patent ID: 8155483

Claim:
An apparatus for measuring height information of an object to be measured using an image captured by an optical system, the apparatus comprising: a CCD camera for capturing the object and outputting the captured image; a lamp for generating white light to illuminate a capturing area of the object; an illumination controller for controlling the lamp to be turned on; a piezoelectric actuator for controlling a minute height of the optical system with respect to the object; an image capturing device for acquiring the image captured by the CCD camera; a driving signal generator for outputting a driving signal to the illumination controller and the piezoelectric actuator when an enable signal is generated from the CCD camera; and an image signal processor for estimating height information of the object from data transmitted from the image capturing unit, wherein the driving signal generator comprises: a memory for storing reference data necessary for the control of generating the driving signal; a digital-to-analog converter; a low pass filter for removing high frequency components from a signal outputted from the digital-to-analog converter and a signal acquired by the image capturing device; and a driving signal generator for generating a driving signal.