This research is concerned with the measurement of surface defects on either hard disk media or hard disk substrates. These defects can effect the performance of a computer disk as the head tracks over the surface. The research concentrates on the measurement of surface defects on computer hard disks using non-contact optical scanning interferometry. The primary objective of the Phase II research is to measure the defects under typical rotating conditions of the disk. The effects of the signal to noise ratio, signal bandwidth, laser spot size, and focusing errors will be studied for different disk rotation speeds. The anticipated result of the Phase II research will be the development of a device for the characterization of one entire side of a computer hard disk surface. There is the potential for a rapid non-contacting measurement technique of surface features of a finished hard disk or uncoated hard disk is the development of new measurement techniques and test equipment that will have the potential to improve the quality of computer hard disks.
