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             ___      ______    ______   _    _   
  ____      / _ \\   /_____//  /_   _// | || | || 
 |    \\   / //\ \\  `____ `    -| ||-  | || | || 
 | [] ||  |  ___  || /___//     _| ||_  | \\_/ || 
 |  __//  |_||  |_|| `__ `     /_____//  \____//  
 |_|`-`   `-`   `-`  /_//      `-----`    `---`   
 `-`                 `-`

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Text this: Compound diffractive lens consisting of fresnel zone plate and frequency selective screen