Research On The Generation And Characteristics Of Optical Vortex During Transmitting

Vortex beams have helical phase structure. There is singularity in the spiral phasecenter. Each photon has the determined number for MH orbital angular momentum.Due to the unique structure，optical vortices has great important application value andpractical significance in the fields of biological science, quantum informationprocessing, atom manipulation, micro manipulation. Optical vortices have beenwidely concerned in recent years. This paper mainly introduces the developmenthistory of optical vortex and the research status of optical vortex, the generationmethod of optical vortex, the interference and diffraction characteristics of light,which lays great emphasis on the introduction of the methods of detecting thetopological charge of vortex beam by using two kinds of special array aperture. Themajor content includes as the following four parts.1. The properties of optical vortices are introduced concisely. The history and themain developments of the optical vortices are reviewed, and their main applicationsand the purpose of the paper are also summarized．2. It outlines the basic theoretical knowledge about optical vortex. Severalgeneration methods of vortex beam is summarized including the geometric opticsmodel transformation method, calculation holography, spiral phase plate, hollowwave guide method liquid crystal spatial light modulation, laser direct output method.The advantages and disadvantages of various methods were also compared.3. It analyses the interference characteristics of optical vortex. This chapterintroduces the interference between the plane wave and vortex beam, spherical waveand vortex beam. I get superposed amplitude intensity distributions of thecorresponding light through changing some important parameters of vortex beams.Then, I get a series of conclusions. These conclusions provide several ideas formeasuring the orbital angular momentum of vortex beams which lays the foundation for further exploration.4. It introduces the diffraction characteristics of optical vortex.Let vortex beamsthrough the annular aperture, diamond aperture, triangular-annular array aperture,square-annular array aperture. Then, I use a kind of mathematical software calledmatlab for computing simulations. I get the different diffraction conclusions of vortexbeams with different topological charge number, and then obtain disciplinaryconclusions. These regular conclusions have laid the foundation for the study of thediffraction characteristics of vortex beams.