Patent ID: 7440188
Filing Date: 2008-10-21
Classification: B23K,G02B

Abstract:
1. A diffractive optical element (DOE) comprising: R×S lengthwise and crosswise aligning pixels {C complex amplitude W(α, β) of a beam diffracted in a direction of a horizontal angle α and a vertical angle β being calculated not by the Fast Fourier Transform but by, where summations are carried out for all the pixels in the DOE and some or all of the diffraction beam angles (α, β) are non-lattice points defined on an object plane, in the case of diverging an incident laser beam into K diffracted beams, the k-th beam having angles (α the angles (α where m both or either of the greatest common divisors U and V being smaller than a quotient λ/aR or λ/bS of the laser wavelength λ divided by a size aR or bS of the DOE, that is,