CPLD-Based Displacement Measurement System for Nanoscale Grating Ruler

Table 2

Cosine error of displacement measurement system of nanoscale grating ruler.

Group	Collection speed	Coarse grating	Fine grating	Switch synthesis (%)
Operating cycle	165.7	55.34	338.7	19.5
Operating hours	215.3	62.88	426.1	36.7
Large range	185.6	71.25	297.4	65.3
Cosine error	203.8	81.61	358.2	75.1