An
ultraviolet laser zoom beam expanding
system, applied to the field of
laser processing, includes a first lens, a second lens, and a third lens (L1, L2, L3). The first lens and the third lens (L1, L3) are plane-convex plus lenses, and the second lens (L2) is a convex-concave minus lens. The first lens, the second lens and the third lens (L1, L2, L3) respectively comprise a first surface and a second surface (S1, S2), a third surface and a fourth surface (S3, S4) as well as a fifth surface and a sixth surface (S5, S6). The radiuses of curvature of the first to sixth surfaces (S1, S2, S3, S4, S5, S6) are ∞, −30, 10, 2.2, ∞, −81. The center thickness of the first to third lenses (L1, L2, L3) is 2, 1, 4. The outer diameters of the first to third lenses (L1, L2, L3) are 10, 3, 34. Proportions of the refractive indexes to the abbe numbers of the first to third lenses (L1, L2, L3) are 1.57:41, 1.48:68, and 1.57:41. An interval (d2) between the second surface and the third surface (S2, S3) is 6-37. An interval (d4) between the fourth surface and the fifth surface (S4, S5) is 114-125, a unit is mm, and a tolerance is 5%. The
system may perform beam expanding on entering light by 2-16 times, which may be adaptable to
laser devices with different emergent diameters and
divergence angles, and improve efficiency and accuracy of
laser processing.