OPTICAL LENS

摘要

An optical lens, comprising a first lens (L1), a second lens (L2), a third lens (L3) and a fourth lens (L4) successively arranged on a common optical axis along the transmission direction of incident light rays. The first lens (L1) and the fourth lens (L4) are meniscus-type negative lenses, the second lens (L2) is a meniscus-type positive lens, and the third lens (L3) is a plano-convex-type positive lens. The optical lens is applied in an optical system of a laser processing device, and when a utilised processing wavelength is different from a monitoring wavelength, imaging colour difference in a monitoring system may be eliminated. In particular, when a wavelength of the far infrared region is utilised as a wavelength for laser processing, and a red light wavelength is utilised as a monitoring wavelength, a better imaging effect is provided in the monitoring system, and laser processing quality is ensured.