Fisheye lens

Abstract

The invention relates to a fisheye lens comprising a first lens group, a second lens group, and a diaphragm. The first lens group comprises a crescent first lens which has negative refractive power and of which the concave surface faces the imaging plane, a second lens which has negative refractive power and of which the image-side surface is concave, a third lens which has positive refractive power and of which the image-side surface is convex, and a fourth lens which has positive refractive power. The second lens group comprises a fifth lens which has positive refractive power and of which both surfaces are convex, a sixth lens which has positive refractive power and of which both surfaces are convex, a seventh lens which has negative refractive power and of which both surfaces are concave, and an eighth lens which has positive refractive power and of which both surfaces are convex. The first lens, the fifth lens, the sixth lens and the seventh lens are glass spherical lenses. The eighth lens is a glass aspheric lens. The fisheye lens provided by the invention has the characteristics of miniaturization and easy realization of magnification chromatic aberration correction. The fisheye lens can match an imaging chip of more than 16 million pixels, and meets the requirement of practical application.

Description

technical field [0001] The invention relates to the technical field of camera lenses, in particular to a fisheye lens. Background technique [0002] In recent years, fisheye lenses have been widely used in fields such as VR (Virtual Reality, virtual reality) cameras, drone cameras, security surveillance cameras, and panoramic cameras due to their advantages of a large field of view, especially in panoramic cameras. , showing almost explosive development in recent years. This has undoubtedly stimulated a huge demand for fisheye lenses. [0003] At present, for panoramic cameras, in addition to meeting the traditional needs of shooting panoramic photos and video recording, most of them are developing in the direction of focusing on VR content production. Compared with ordinary cameras, a new type of panoramic camera must not only meet the basic factors such as accurate color reproduction of the camera, low brightness and no noise, but also an important criterion for judging,...

AI Technical Summary

Problems solved by technology

At present, the panoramic cameras for professional applications with better resolution are very expensive, and the resolution of some consumer-grade panoramic cameras cannot meet the actual needs of users.

[0004] In addition, in order to obtain high-resolution imaging, large wide-angle fisheye lenses must be corrected for chromatic aberration of magnification. However, in the existing technology, many fisheye lens manufacturers use many plastic aspheric lenses in fisheye lenses in order to reduce costs. , and there are few types of plastics, so the correction magnification is difficult to achieve, and plastics are sensitive to temperature, so it is difficult for fisheye lenses to be suitable for high or low temperature occasions

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