Laser ignition tube with sealing structure

The invention discloses a laser ignition tube of a sealing structure. The laser ignition tube comprises an ignition tube shell, a lens assembly and an O-shaped ring. The lens assembly is installed on the ignition tube shell and fixed through laser welding. The O-shaped ring is arranged in a position gap between the lens assembly and the ignition tube shell; the lens assembly comprises a lens seat, a metalized self-focusing lens and a brazing material. The metalized self-focusing lens is welded in the lens holder through a brazing material, and the lens holder is fixed in the ignition tube shell through laser welding; the metalized self-focusing lens comprises an antireflection film, a selective reflection film, a metal film and a self-focusing lens, the upper end face of the self-focusing lens is plated with an antireflection film, the lower end face is plated with a selective reflection film, and the cylindrical end face is evaporated with a metal film. The laser ignition tube of the sealing structure is sim