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Edge topography measurement technology is vital in many engineering applications such as cutting tool inspection, photomask inspection, or corrosive wear inspection. Although those applications require high-level sharpness or smoothness of the edges to achieve their needs, there is little measurement and inspection technology available. Most of the current surface metrology and inspection technology is primarily focused on planar surface characterization [1-3], and sometimes indirect methods such as measuring the cutting force or acceleration to interpret tool wear propagation during the machining process are used [4]. This paper presents the enhanced knife-edge interferometry (KEI) that measures optical scattering behaviors that originated from the edge. KEI utilizes the optical interference of incident light and scattered light at the edge and produces the fringe patterns proportional to edge quality [5-7]. Analysis of such fringe patterns enables monitoring edge quality. We recently improved KEI performance by shaping the beam with the objective lens (4×, 10×). The incident plane wave was turned into a spherical wave by the objective lens, and the spherical wave and the diffracted wave at the edge interfered. As a result, the strong interference effect was observed, and over 3 times fringe patterns were obtained compared to the interference results of no objective case. The enhanced KEI was employed for edge quality inspection of sharp edges (razor blade), cutting tools, and photomask.
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REVIEW OF KEI METHOD-BASED DIMENSIONAL MEASUREMENT, POSITIONING CONTROL AND PART INSPECTION
This paper reviews knife-edge interferometry (KEI) capable of inspection and metrology for various engineering applications, including displacement measuring sensors for dynamic system controls and edge quality of the parts, such as cutting tools, corrosive blades, and photomask patterns. This paper includes the modeling, design, and data analysis of KEI. With the expanding market of manufacturing industries, edge topography and instrumentation technology become more and more vital to industrial manufacturing-related applications such as cutting tool wear inspection, photomask edge roughness determination, and edge corrosion propagation monitoring. Due to the limitation of measurement requirements like non-contact (photomask inspection), in-situ (cutting tool inspection), and real-time (corrosion propagation monitoring), there are only a few methods available in the market above, and those methods are based on post-processing. The KEI is capable of on-machine measurements, especially for the nanopositioning systems, providing a large working range and positioning accuracy compared with the conventional displacement sensor. This review addresses the current and future KEI technology. Here, including the theoretical approaches to KEI, this review details the data analy
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- Award ID(s):
- 1855473
- PAR ID:
- 10334501
- Date Published:
- Journal Name:
- Manufacturing Engineering and Science Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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