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           _    _    _    _    __   __            
    ___   | || | || | \  / ||  \ \\/ //   ____    
   /   || | || | || |  \/  ||   \ ` //   |    \\  
  | [] || | \\_/ || | .  . ||    | ||    | [] ||  
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    -|_||   `---`   `-`  `-`     `-`'    |_|`-`   
     `-`                                 `-`

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Text this: Generation of radially polarized beam with a segmented spiral varying retarder