Telecentric F-theta optical lens and optical system

Abstract

The present invention relates to a telecentric F-theta optical lens and an optical system; the optical lens comprises a first lens, a second lens, a third lens and a four lens, which are arranged in sequence along an incidence direction; the first lens is a double concave negative lens; the second lens is meniscus positive lens with a curved surface toward the incidence side; the third lens is a plane convex positive lens or a double convex positive lens; the fourth lens is a convex plate positive lens or a double convex positive lens. Besides, preferably the optical power of each lens and the system optical power of the optical lens satisfy that: f1 / fw is more than -0.65 and less than -0.55, f2 / fw is more than 1.6 and less than 2.5, f3 / fw is more than 0.8 and less than 1.2, f4 / fw is more than 2.2 and less than2.5, wherein, f1, f2, f3 and f4 are the optical powers of the first lens, the second lens, the third lens and the fourth lens respectively; fw is the system optical power of the optical lens; by arranging the four lenses to be a 'negative-positive-positive-positive' separated optical power system, the exit pupil position of the F-theta optical lens is positioned at an afocal position, and the image main light in the field of view is parallel mutually and perpendicular to the imaging surface. Besides, the astigmatism and the field curvature of the system are regulated perfectly, the imaging on the whole field of view is uniform, and no vignetting exists.

Description

【Technical field】 [0001] The invention relates to an optical lens, in particular to a telecentric F-theta optical lens suitable for laser application and an optical system using the optical lens. 【Background technique】 [0002] With the continuous advancement of science and technology, laser applications have penetrated into every aspect of our modern life. For example, laser marking machines have gradually replaced various traditional printing machines and silk screen printing machines due to their advantages such as fast speed, strong flexibility, no consumables, and permanent marking. In addition, with the development of industry, the field of laser application is also expanding, and various laser applications including laser scribing, laser cutting, and laser drilling are gradually being widely used due to their excellent processing quality. [0003] F-theta optical lenses are used in many laser applications such as laser marking, laser scribing, laser cutting, and lase...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the technical problem that the principal ray of the image side of the F-theta optical lens in the prior art forms a certain inclination angle with the imaging surface, which makes the processing edge obliquely deformed, the present invention proposes an image with the exit pupil located at infinity and the field of view Telecentric F-theta optical lens and optical system with square principal rays parallel to each other and perpendicular to the imaging plane

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