Visual Inspection Technology in the Hard Disk Drive Industry [Hardcover]

A presentation of the use of computer vision systems to control manufacturing processes and product quality in the hard disk drive industry. Visual Inspection Technology in the Hard Disk Drive Industry is an
application-oriented book borne out of collaborative research with the world’s leading hard disk drive companies. It covers the latest developments and important topics in computer vision technology in hard disk drive manufacturing, as well as offering a glimpse of future technologies.

PREFACE xi

CHAPTER 1. FEATURE FUSION METHOD FOR RAPID CORROSION DETECTION ON POLE TIPS 1
Suchart YAMMEN and Paisarn MUNEESAWANG

1.1. Introduction 2

1.2. Algorithm for corrosion detection 6

1.2.1. Extraction of top-shield region 6

1.2.2. Area-based feature 9

1.2.3. Contour-based feature 13

1.3. Experimental result 19

1.3.1. Distribution of corrosion 20

1.3.2. Performance metric 20

1.3.3. Robustness 24

1.4. Conclusion 27

1.5. Bibliography 28

CHAPTER 2. NONLINEAR FILTERING METHOD FOR CORROSION DETECTION ON POLE TIPS 33
Paisarn MUNEESAWANG and Suchart YAMMEN

2.1. Introduction 33

2.2. Perpendicular magnetic recording 35

2.3. Perpendicular magnetic recorder and corrosion 37

2.3.1. Lubricant layer 38

2.3.2. Thermal effect results in corrosion 41

2.3.3. Recording head/slider manufacturing and corrosion 42

2.4. Length estimator for pole tip 44

2.5. Nonlinear filtering as a corrosion detector 48

2.5.1. Median filter tló,