Deep sub-micro flying height measuring technologies and system

This paper describes a technique for the measurement of deep sub-micron flying height based on intensity interferometry, focuses on the introduction of operating principles, system configuration and image visual feedback techniques. Because the flying height is super low, micro pitch or roll of the slider will lead to measuring error. Thus a constant relative position between the optic spot and the slider should be assured. Imaging processing technique is used to obtain the coordinates of both the slider and the optic spot. A detection algorithm of the center of circle is detailed in this paper.