Uncertainty Estimation 𝑈(𝐿_𝑔+𝐿_𝑤) due to Geometrical Imperfection and Wringing in Calibration of End Standards

Table 1

Standards specifications and measured results of GBs (grade 0).

Nominal length (L), mm		Tolerance on length; = 0.12 μm + 2 × 10^−6 L, μm		Tolerance on parallelism; = 0.10 μm + 3 × 10^−7 L, μm
Range	Referenced	Theoretical	Average measured error	Theoretical	Average; measured error
0.5→50	6.5	+0.10→−0.10	+0.11	+0.10→−0.10	0.06
	30.0		+0.14	+0.10→−0.10	0.07
50→150	60.0		+0.09	0.12	0.07
	90.0	+0.30→−0.30	+0.20	0.12	0.10