Understanding Scratch and Dig Specifications

Level: Introductory Length: 4 hours Format: In-Person Lecture Intended Audience: This material is intended for anyone who needs specify, quote, or evaluate optics for surface imperfections. Those who either design their own optics or who are responsible for optics quality control will find this course valuable. Description: Surface imperfection specifications (i.e. Scratch-Dig) are among the most misunderstood, misinterpreted, and ambiguous of all optics component specifications. This course provides attendees with an understanding of the source of ambiguity in surface imperfection specifications, and provides the context needed to properly specify surface imperfections using a variety of specification standards, and to evaluate a given optic to a particular level of surface imperfection specification. The course will focus on the differences and application of the Mil-PRF-13830, ISO 10110-7, and ANSI OP1.002. Many practical and useful specification examples are included throughout, as well as a hands-on demonstration on visual comparison evaluation techniques. The course is followed by SC1017 Optics Surface Inspection Workshop, which provides hands-on experience conducting inspections using the specification information provided in this course. Learning Outcomes: This course will enable you to: - describe the various surface imperfection specifications that exist today. - identify the different illumination methods and comparison standards for evaluation. - demonstrate a surface imperfection visual inspection. - compose a meaningful surface imperfection specification for cosmetic imperfections using ISO, ANSI, or MIL standards. - understand the options available for controlling surface imperfections in a vendor/supplier relationship. Instructor(s): David M. Aikens a.k.a "the scratch guy", is among the foremost experts on surface imperfection standards and inspection. Dave is President and founder of Savvy Optics Corp., and is the Chair of the US Technical Advisory Group for TC172 for Optics and Photonics standards. Event: SPIE Optifab 2023 Course Held: 16 October 2023