Studies On The Modulation And Focus Of High-order Vector Optical Field

The vector field with complex spatial structure is the important research in the modulation of optical fields.Ince-Gaussian(IG)vectorial optical field and complex high-order ring vectorial field is included in our research,our study discussed the generation of high-order IG vectorial field and the focus of complex high-order ring vectorial field.As the intrinsic optical field which is based on the elliptic coordinate system,IG mode has richer spatial degrees of freedom than others,and it is the fundamental optical field to conduct a complex-spatial-structure vector field.On the basis of various kinds of vector fields and IG scalar fields,two methods to approach IG vectorial field is verified in the essay.One of them is modulating even and odd modes by a spatial light modulator and a Wollaston prism in parallel,another is controlling four degrees of freedom(amplitude,phase,polarization,retardation)of the expected IG vectorial mode by the vectorial optical field generator(VOF-Gen)in series.The superposition of orthogonal polarized IG even and odd modes or modulation of the four degrees of freedom to generate the IG vectorial mode is discussed during the experiment.Experimental results are studied and compared with the simulated results,indicating the feasibility of generating IG vectorial fields by modulating separately in parallel and in series.High-order ring radially polarized beam and azimuthally polarized beam are basic optical fields to generate long focal depth optical needle field and diffraction-limited optical tube field.Complex high-order ring vectorial field can be constructed by splicing these two optical fieldsp-(we can divide them into sectors)together.The focus,the intensity and the distribution of polarization of different structures of complex vectorial field with high numerical aperture(NA)are summarized.Our results can be the reference of how to get a complex vectorial optical field which has a long focal depth and a complicated structure.