PROBLEM TO BE SOLVED: To efficiently treat an affected part in a treatment range by scanning a laser beam from a light source in the treatment range at a high speed by a laser treatment device.SOLUTION: A laser treatment device 1 for treating an affected part Ka by irradiating an affected part Ka with a laser beam Ls includes: a light source 10 (light source device) for outputting the laser beam Ls； a polarization variable device 20 for polarizing the laser beam Ls output by the light source 10； and a scanner 40 for scanning the laser beam Ls polarized by the polarization variable device 20 in a treatment range K including the affected part Ka and irradiating it (a first crystal element 42 for scanning the laser beam Ls in a horizontal direction and a second crystal element 46 for scanning the laser beam Ls in a vertical direction through a wavelength plate 44). The scanner 40 includes crystal elements that change an emission direction of the laser beam Ls according to an applied input voltage V (electric field).SELECTED DRAWING: Figure 1COPYRIGHT: (C)2019,JPO&INPIT
