| 摘要 |
An apparatus for generating a ring-shaped beam is provided to facilitate manufacture thereof and improve mechanical stability. An apparatus for generating a ring-shaped beam includes a first surface(913), and a second surface(925). A refractive index of an axicon is n1, and a refractive index of a medium around the axicon is n2. The refractive index of the axicon is larger than the medium(n1>n2). A laser beam parallel to an optical axis enters the first surface of the apparatus. The beam has a radius r. A height h1 of a first laser beam(931) from the optical axis is smaller than the radius r of the beam(h1<=r). The first laser beam is refracted at one point P1 on the first surface to be a second laser beam(933). |
