Image Measurement of Micro-hole with linear CCD

摘要

It is difficult to measure micro-hole by means of project or light-sectioning. Irradiated by the collimated laser beam, a hole less than 0.5mm will result in an Airy spot because of diffraction, the Airy spot is measured by linear array CCD. A solution was given to define the diffusion state of diffraction image s edge, and two mathematical methods was presented to calculate inspection results in this paper. The first method is to integrate optoelectric signals from scanning sample spots, and the other is to calculate digital data with least square method by computer. Thus, the detection accuracy has been improved obviously.