Determination the allowable error to adjustment of a diffractive optical element and the accuracy demanded to set the parameters of the focused beam

Abstract

Diffractive optical elements capable of transforming the wavefront in a predetermined manner, with high efficiency may be apply in recording systems and reading information, and also its transmission in the optical range. To improve the efficiency use of diffractive optical elements is expedient to determine the requirements for their adjustment and the accuracy of beam setting parameters forming. As an example, considered the use of a diffractive optical element for transmitting high-power laser beam for the purpose to conducting the appropriate heat treatment of the process object. It was determined that the permissible error of alignment of the optical element is no more ΔU1 = ΔV = 0.18·10-3 m, the accuracy of the focused beam parameters should not be lower ΔrΦ/rΦ = 3.1 %; ΔRΦ/RΦ = 2%, and the permissible value of rotation angle Φ error of the diffractive optical element is ΔΦ = 2.30. To solve this problem a diffractive optical element is characterized by adequate values of allowable errors. Keywords: diffractive optical element, laser beam, adjustment, accuracy