Inspecting with Optical Comparators 351

Inspecting with Optical Comparators provides an overview of the optical comparator, which uses optics to project an enlarged, two-dimensional shadow of a part onto a glass screen for measurement of its length, width, and surface. Simple optics display the part upside down and backwards. Corrected optics display the part right side up and backwards. Fully corrected optics yield an image identical to the part orientation. Regardless of type and complexity, all optical comparators measure by comparison, screen rotation, and motion. If optical comparators are properly maintained, measurement error is the result of the operator. By understanding the components and measurement methods of the optical comparator, operators can avoid unwanted variation. Variation in measurement can lead to faulty parts passing inspection and reaching consumers. After completing the class, users will be able to describe best practices for using the optical comparator to inspect parts.