Prime lens

Abstract

The embodiment of the invention discloses a prime lens, which comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with positive focal power or negative focal power, a diaphragm, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power and a seventh lens with positive focal power whichare sequentially arranged along an optical axis from an object side to an image side, wherein the first lens and the third lens are spherical lenses, and the second lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are aspheric lenses. According to the technical scheme of the embodiment of the invention, the 4K wide-angle optical lens with a large target surface and an ultra-large aperture can be realized, the lens supports the maximum target surface of 1/1.8 inches under the condition of relatively low cost, the aperture number meets the condition that F is more than0.8 and less than 1.2, the field angle is greater than 120 degrees, and the imaging requirement is met when the lens is used in an environment of -30 DEG C to 80 DEG C.

Description

technical field [0001] Embodiments of the present invention relate to lens technology, and in particular to a fixed-focus lens. Background technique [0002] With the rapid development of science and technology, people have a higher level of understanding of security, and surveillance cameras were born immediately. In recent years, surveillance cameras have become a major force in the security industry, driving the continuous advancement and rapid development of the security industry. [0003] With the increasing development of security monitoring systems, the requirements for security lenses are getting higher and higher, mainly reflected in higher image quality, larger field of view, larger aperture and larger target surface. At present, the existing ultra-large aperture lens often has a small field of view, generally less than 120°, and the target surface is generally 1 / 2.7 inches. However, in the field of security monitoring, a larger field of view means a wider monitor...

AI Technical Summary

Problems solved by technology

Therefore, it is necessary to develop a 4K wide-angle optical lens with a large target su...

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