Course SC700

Understanding Scratch and Dig Specifications

Wednesday, 1 February 2023 • 8:30 AM - 12:30 PM PST
Level: Introductory
Member: $495.00
Non-member: $570.00
Student member: $258.00
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

  • describe the various surface imperfection specifications that exist today.
  • compose a meaningful surface imperfection specification for cosmetic imperfections using ISO, ANSI, or MIL standards.
  • identify the different illumination methods and comparison standards for evaluation.
  • demonstrate a surface imperfection visual inspection.
  • understand the options available for controlling surface imperfections in a vendor/supplier relationship.


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.


David M. Aikens - Savvy Optics Corp. (United States)
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.

Additional notes

COURSE PRICE INCLUDES a copy of the latest ANSI approved surface imperfections specification standard. Attendee Testimonial:
Instructor was personable, knowledgeable and passionate. Answered all questions and facilitated learning.
Good job at breaking down more advanced topics on statistics/distributions into an easy to follow format. Great insight into how tolerencing plays into manufacturing.