Abstract: Provided are a laser cutting device and a laser cutting method. The laser cutting device comprises a beam expanding element provided with a plurality of lens sets, wherein optical axes of the plurality of lens sets are located in the same line and each lens set comprises at least one lens; the beam expanding element is configured to convert an incident beam into a first beam; and a spectroscopic element arranged on a light path of an emitted light of the beam expanding element, and wherein the spectroscopic element is configured to convert the first beam into multiple second beams that are annular and spaced apart from each other.

Abstract: A femoral neck measuring method includes: measuring an affected limb after a femoral stem prosthesis is installed through an optical localization probe, and calculating an actual length of the femoral neck needed by the affected limb according to an osteotomy surface of the affected limb determined after the femoral stem prosthesis is installed; determining a femoral ball prosthesis and a femoral neck prosthesis to be selected according to the calculated actual length of the femoral neck and a length of a femoral neck of a healthy limb measured before surgery; and measuring a length of the affected limb after the femoral ball prosthesis and the femoral neck prosthesis are implanted, and restraining a length difference between the healthy limb and the affected limb by adjusting a length of the femoral neck of the affected limb.