Fig. 1. Geometry and notation of generic MPI consisting of N points, uniformly distributed over a circle of radius a. The points are indicated by white dots and the angular coordinate of the n-th point is α_n = 2π nN⁻¹.

Fig. 2. Simulated far-field intensity patterns behind multipoint interferometer of N points illuminated by AV beam with topological charge l.

Fig. 3. Simulated far-field intensity patterns behind MPI with N points illuminated by AV beam with topological charge l, with patterns for l = |m| and l = – |m| being mirrored in x axis.

Fig. 4. (a) Displacement of MPI with respect to propagation axis of impinging beam with d for N = 6, and (b) MPI axis tilted with respect to the propagation axis of the impinging beam with θ for N = 6.

Fig. 5. Far-field intensity patterns behind a multipoint interferometer for N = 5 illuminated by AV with l = 2 displacement and tilt of the multipoint interferometer with respect to the propagation axis of impinging beam with (a) d = 0 mm with θ from 0° to 20°, (b) d = 0.3 mm with θ from 0° to 20°, (c) d = 0.6 mm with θ from 0° to 20°, and (d) d = 0.9 mm with θ from 0 ° to 20°. A displacement and a tilt of the multipoint interferometer with respect to the propagation axis of the impinging beam result in distorted and blurred interference patterns.