The wedge prism can be used to deflect the laser beam to a certain angle alone, or the combination of two wedge prisms can be used as beam deflection. A single prism can shift the incident beam by a certain angle. Two wedge-shaped prisms can be used as deformable prisms (to correct the elliptical beam output from the laser tube) or to deflect the beam at various angles in the range of 4 θ, which refers to the light deflected by a single prism. This beam shaping is achieved by rotating two wedge-shaped prisms respectively, which is typically used for scanning different positions of beams in imaging.