Monitoring lens

Abstract

The invention relates to a monitoring lens. From one side facing an object, the monitoring lens is provided with a first lens element, a second lens element, a third lens element, a diaphragm, a fourth lens element and a lens component in turn, wherein the first lens element has negative focal power, faces an object convexly, and is in a crescent shape; the second lens element has the negative focal power and is in a concavo-concave shape or the crescent shape; the third lens element has positive focal power and is in the concavo-concave shape; the diaphragm is arranged behind the third lens element; the fourth lens element has the positive focal power and is in concavo-concave shape; the lens component is formed by jointing a fifth lens and a sixth lens and has the positive focal power, wherein the fifth lens element having the positive focal power is close to the fourth lens element; and the sixth lens element having the negative focal power is positioned behind the fifth lens element. The invention provides a day and night dual-purpose high-resolution monitoring lens which has a compact structure, a large viewing angle, high imaging quality, non-focal plane drift of visible light and near infrared light, and low production process requirement aiming at overcoming the defect in the prior art.

Description

【Technical field】 [0001] The invention relates to a day and night high-definition security monitoring lens system, which is especially suitable for a security monitoring camera and a driving recorder image system for monitoring an object under low illumination at night. 【Background technique】 [0002] With the rapid rise of the security monitoring market this year and the optimization and improvement of digital processing and network transmission speeds, the quality requirements for security monitoring lenses have been greatly improved, from ordinary monitoring requirements to high-definition identification. The use of near-infrared auxiliary lighting in low-light dark field environments also requires clear and sharp images. [0003] At present, the security monitoring lens is generally composed of 4 to 8 lenses, but this kind of wide-angle security monitoring lens is large in size, and the resolution cannot meet the needs of CCDs with more than one million pixels, and the i...

AI Technical Summary

Problems solved by technology

[0003] At present, the security monitoring lens is generally composed of 4 to 8 lenses, but this kind of wide-angle security monitoring lens is large in size, and the resolution cannot meet the needs of CCDs with more than one million pixels, and the image quality in low-light environments is even blurred. Customers request small size and high performance requirements

Therefore, the plastic aspheric surface technology is used to reduce weight, cost and deformation, but its light transmission performance is weak, the mold technology requirements are strict, and it is greatly affected by the external environment temperature, which cannot meet the requirements of maintaining a more perfect imaging definition.

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