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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.