Day-and-night dual-purpose lens system free of day-and-night confocal design and implementation method thereof

Abstract

The invention relates to a day-and-night dual-purpose lens system free of day-and-night confocal design and an implementation method thereof. The day-and-night dual-purpose lens system comprises a lens, a chip and a light filter switcher, wherein the light filter switcher is arranged inside the lens or is arranged at the front end of the lens or is arranged between the lens and the chip; a light filter I and a light filter II used for days and nights respectively are arranged on the light filter switcher; the light filter I and the light filter II are vertical to an optical axis and can be switched to the position of the optical axis for filtering light with different wave bands respectively; the light filter I is an infrared light cut-off filter capable of filtering infrared light; and the light filter II is a visible light cut-off filter capable of filtering visible light. The system and the method do not need to take a complicated day-and-night confocal design of the lens into account, a day-and-night confocal effect can be realized through a simple structure or method, and the system is low in manufacturing cost and excellent in performance.

Description

technical field [0001] The invention relates to the technical field of optical devices, in particular to a day and night dual-purpose lens system without day and night confocal design and a realization method thereof. Background technique [0002] At present, in the field of day and night dual-use surveillance lenses, the main problems that need to be solved are the day and night confocal problem and the cost performance problem. [0003] When the monitoring lens works 24 hours a day and at night, there are currently two ways to use it: 1. The use of day and night switching states; 2. The use of low-light cameras and lenses. [0004] The first scheme is the most widely used one at present. However, due to the dispersion of the optical material itself, that is, the refractive index of the same optical material is different in the visible light band and the infrared light band, this often causes the lens to be out of focus day and night, which leads to a lot of lenses in the ...

AI Technical Summary

Problems solved by technology

However, this solution generally needs to use low-dispersion glass, or increase the number of lenses to increase the complexity of the optical system to achieve day and night confocal, which greatly increases the cost

Moreover, it is difficult to completely eliminate chromatic aberration during the implementation of this solution, and there will be a defocus of 0.01-0.02mm or even greater, which cannot truly achieve high-definition effects in both day and night modes; at the same time, this solution In the process of correcting defocus, it is easy to produce obvious blue-purple fringing phenomenon

[0006] In view of this, how to ensure the daytime effect and solve the night vision problem at a low cost, there is no good solution in the market at present

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