Glass-plastic mixed fisheye lens

Abstract

The invention relates to the technical field of lenses. The invention discloses a glass-plastic mixed fisheye lens. The glass-plastic mixed fisheye lens comprises six lenses. A first lens is a convex-concave lens with a negative refractive index. A second lens is a convex-concave lens or a concave-concave lens with negative refractive index. A third lens has a positive refractive index and the object side surface is a convex surface. A fourth lens is a concave lens with negative refractive index. A fifth lens and the sixth lens are convex lenses with positive refractive indexes. The object side surfaces and the image side surfaces of the second lens and the sixth lens are aspheric surfaces. The second lens and the sixth lens are made of plastic materials. The first lens, the third lens, the fourth lens and the fifth lens are made of glass materials, and the fourth lens and the fifth lens are mutually glued. The lens has the advantages of short total length and low cost. The resolutionis high, and the imaging quality is good. The image surface is large, and the confocal property of visible light and infrared light is good.

Description

technical field [0001] The invention belongs to the technical field of lenses, in particular to a glass-plastic hybrid fisheye lens. Background technique [0002] A fisheye lens is an ultra-wide-angle lens with a focal length of 16mm or less. The front lens of this lens has a large diameter and protrudes toward the front of the lens in a parabolic shape, which is quite similar to the eyes of a fish, so it is commonly known as a "fisheye lens". At present, fisheye lenses have been widely used in security monitoring, vehicle and other fields. Therefore, the requirements for fisheye lenses are getting higher and higher. [0003] However, there are still many shortcomings in the current fisheye lenses on the market. For example, most of them use all-glass lenses, and the cost is high; the total length of the lens system is relatively large, generally greater than 13mm; the image surface is small, less than 5mm; the size is small and the image surface is large The lens, its poo...

AI Technical Summary

Problems solved by technology

[0003] However, there are still many shortcomings in the current fisheye lenses on the market. For example, most of them use all-glass lenses, and the cost is high; the total length of the lens system is relatively large, generally greater than 13mm; the image surface is small, less than 5mm; the size is small and the image surface is large The lens, its poor infrared confocal performance, etc., can no longer meet the increasing requirements, and it is necessary to improve it

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