The workhorse of modern metrology. Types:
Length = 50.002 mm Combined standard uncertainty, u_c = 0.0015 mm Expanded uncertainty, U = 0.0030 mm (k=2) → True value lies between 49.999 mm and 50.005 mm with 95% confidence. metrology engineering
The Invisible Backbone of Quality: Why Metrology Engineering Matters The workhorse of modern metrology
No measurement is exact. quantifies the range within which the true value lies (e.g., 10.002 mm ± 0.003 mm with 95% confidence). Errors can be systematic (bias) or random (noise). u_c = 0.0015 mm Expanded uncertainty