Measuring Appearance Characteristics of Anodized Aluminum Automotive Trim

In evaluating appearance of anodized aluminum, the most important kinds of glossiness are commonly termed distinctness of image, bloom, and haziness. To obtain a simple, meaningful set of quantitative numbers, the various kinds of glosses are related to specific portions of a goniophotometric curve. The technique is applicable to mirror-like metal finishes, to etched and patterned metal surfaces, and to ceramic and paint coatings. This method agrees well with visual ratings, is sensitive to minimum visually detectable differences within products, and provides a means for numerically classifying different products without need for material standards for calibration.