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We present a method of phase modulation on the incident beam of the optical system to obtain a super-resolution focused spin spot by a multibelt binary optical phase element. We investigate the focusing properties of various structured lights from three situations: vortex beam, vector beam, and scalar beam, including the azimuthally polarized optical vortex beam (APOV), radially polarized beam (RP) and circularly polarized beam (CP). Under the same numerical aperture and the premise of ensuring the longitudinal uniformity of the focused field, we optimize the belt spacing of the multibelt binary optical phase element to obtain the optimal solution for each beam by the simulated annealing algorithm. The full-width at half-maximum (FWHM) of the focused spot of the APOV is the smallest. And the focused spot of the RP is second smallest. Particularly, the modulated focused APOV has an extremely small spin spot with pure transverse polarization. Its spin texture is similar to that of the Bloch-type magnetic skyrmion in the central region without the modulation. This kind of focused spin spot super the diffraction limit has potential in the applications of super-resolution imaging, circular dichroism imaging, chiral imaging, and the screening and manipulation of chiral particles.
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