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J. Eur. Opt. Society-Rapid Publ. 22, 36( 2026)
Figure 13. Measurement of the fringe movement D / while moving the stage along x-axis with Dx over time. Two steps forward and backward with 400 nm with a velocity of 27 nm / s are performed.
Figure 14. Measurement of the fringe movement D / over stage movement Dx, corresponding to Figure 13.
Figure 15. Measurement of the fringe movement D / over Dx. The orientation angle c is aligned to minimize the gradient m x of the linear fit.
Figure 16. Measurement of D / and the stage movement Dy perpendicular to the fringe orientation over time. Five steps were performed over a total period of 90 s.
m z is the linear gradient of the offset shift, a is the amplitude of the intensity modulation, x the spatial frequency of the modulation, u 0 the initial phase of the modulation and c an initial phase offset. The gradient m z is determined by performing a fit withEq.( 21). The gradient is then used to calculate the tilt angle with