The lens comprises a lens body, the
peripheral wall of the lens body is a total reflection surface, a groove for containing a
light source is formed in the bottom wall of the lens body, the
peripheral wall of the groove forms a first incidence surface, the top wall of the groove is concaved upwards to form a second incidence surface, a pit is formed in the middle of the top wall of the groove, and the top wall of the pit forms a third incidence surface. The top wall of the lens body forms a first emergent face, a first emergent portion is arranged in the middle of the first emergent face, the top wall of the first emergent portion is concave inwards to form a second emergent face, a second emergent portion is arranged in the middle of the second emergent face, the top wall of the second emergent portion is concave inwards to form a third emergent face, the third emergent face is an arc face formed by rotation of a convex arc, and the second incident face is arranged below the second emergent face. According to the scheme, the main light spots and the auxiliary light spots with clear transition boundaries are formed through the
single lens, the light and shade alternating illumination effect is achieved, the main light irradiates the main light spots of the main exhibits, the auxiliary light spots irradiate the accompanying articles on the peripheries of the main exhibits, and the spatial layering sense is improved.