A high and low temperature infrared confocal, large aperture, small volume optical system

Abstract

The invention discloses an optical system, which includes a diaphragm, a photosensitive chip and a filter. A first lens group that can move relative to the diaphragm is provided on the side of the diaphragm close to the object side. A second lens group is arranged between the diaphragm and the filter. Two lens groups, a third lens group capable of moving relative to the second lens group is provided between the second lens group and the optical filter, the first lens group includes a first lens, a second lens, a third lens, and a fourth lens, The focal lengths of the first lens, the second lens and the third lens are all negative, the focal length of the fourth lens is positive, the second lens group includes the fifth lens and the sixth lens, the focal length of the fifth lens is positive, and the focal length of the sixth lens is positive. The focal length is negative, the third lens group includes the seventh lens and the eighth lens, the focal length of the seventh lens is negative, the focal length of the eighth lens is positive, the first lens, the second lens, the third lens and the seventh lens are all A meniscus lens with the concave surface facing the image side. The invention has high and low temperature, infrared confocal, high pixel, low cost, large aperture and small volume.

Description

[0001] 【Technical field】 [0002] The invention relates to an optical system, more specifically a high and low temperature infrared confocal, large aperture, and small-volume optical system. [0003] 【Background technique】 [0004] At present, the lenses used in surveillance generally have such shortcomings: poor adaptability to high and low temperature, non-confocal infrared, high cost, small aperture, and large volume. Specifically, existing zoom lenses generally do not have infrared confocal function because they can be adjusted in focus, and have poor adaptability to high and low temperatures. When the image is cleared during the day, the image will appear blurred in the infrared at night, or the temperature during the day is relatively low. High, even when the temperature is low at night, the picture is blurred, and someone needs to assist in focusing from time to time, which is a serious waste of human resources. Moreover, the current high-pixel surveillance lens is prone...

AI Technical Summary

Problems solved by technology

[0004] At present, the lenses used in monitoring generally have such shortcomings: the lens has poor adaptability to high and low temperature, infrared non-confocal, high cost, small aperture, large volume, etc.

Specifically, existing zoom lenses generally do not have infrared confocal function because they can be adjusted in focus, and have poor adaptability to high and low temperatures. When the image is cleared during the day, the image will appear blurred in the infrared at night, or the temperature during the day is relatively low. High, even when the temperature is low at night, the picture is blurred, and someone needs to assist in focusing from time to time, which is a serious waste of human resources. Moreover, the current high-pixel surveillance lens is prone to imbalance in image sharpness and color reproduction, and the image quality is poor.

At present, there are only a few lenses that improve a certain characteristic at the expense of other characteristics. For example, in order to achieve high and low temperature, infrared confocal and high pixels, a large number of glass spherical lenses or glass aspherical lenses are used, which improves the performance of the lens. cost, unable to meet the low-cost needs of consumers

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