Patent ID: 9289853
Filing Date: 2016-03-22
CPC Classification: B23K

Claim Text:
1. A laser beam applying apparatus, comprising: laser beam oscillating unit for oscillating a laser beam; a focusing lens for focusing said laser beam oscillated by said laser beam oscillating unit; a diffractive optic element provided between said laser beam oscillating unit and said focusing lens for defining a spot shape of said laser beam oscillated by said laser beam oscillating unit; and zeroth-order light removing unit for removing zeroth-order light emerged from said diffractive optic element and leaving only first-order light whose spot shape has been defined by said diffractive optic element to said focusing lens, said zeroth-order light removing unit including: wherein said incident surface of said first prism is set so that said first-order light passed through said diffractive optic element is perpendicularly incident on said incident surface; said emergent surface of said first prism and said zeroth-order light reflecting surface of said second prism are set parallel to each other; said incident surface of said first prism and said first-order light emerging surface of said second prism are set parallel to each other; and said first-order light whose spot shape has been defined by said diffractive optic element is led to said focusing lens by said zeroth-order light removing unit so that the spot shape of said first-order light is maintained.