Measurement of Small Holes

doi:10.1117/3.2513685.ch10

Book: Practical Optical Dimensional Metrology

Author(s): Kevin G. Harding

Published: 2019

https://doi.org/10.1117/3.2513685.ch10

Abstract

Manufacturing methods and tolerances have continually improved during recent years. Applications ranging from cooling channels and circuit boards to ink jet print heads are using holes that can be well under a millimeter in size. To keep up with smaller features and tighter tolerances, measurement tools have also had to adapt. This chapter reviews tests on potential optical metrology methods as applied to submillimeter-size holes. A focus-based method provided the most promise for detailed inner-profile mapping of small holes.