Camera shooting method and device of day and night lens without IR-Cut (infrared-cut) switcher

Abstract

The invention relates to a camera shooting method and device of a day and night lens without an IR-Cut (infrared-cut) switcher. An optical light-transmitting element in front of, in the middle of or behind the lens is plated with a filter coating, or the optical light-transmitting element provided with the film coating is additionally arranged in front of, in the middle of or behind the lens; the filter coating has the characteristics that transmittance of light with the wavelength of 400-640 nm or 840-970 nm is increased, the average transmittance of the light with the wavelength of 400-640 nm or 840-970 nm is higher than 98%, light with the wavelength of 670-800 nm is cut off and the average transmittance of the light with the wavelength of 670-800 nm is lower than 0.4%; moreover, a color correction unit with functions of separating and eliminating infrared component signals in image signals is additionally arranged in an image signal processor connected with an image sensor. The method and the device can radically solve a problem of slight red images shot by a camera at day time without the IR-Cut switcher, truly realize day and night use of the lens, and can guarantee that the lens is reliably used.

Description

technical field [0001] The invention relates to the fields of security, home security, and home intelligence, in particular to a camera method and device for a day and night dual-purpose lens without an IR-Cut switcher. Background technique [0002] As we all know, traditional security cameras must be equipped with IR-CUT as standard to switch between day and night. During the day, use the infrared filter inside the IR-CUT to filter out the infrared component to achieve the true color of the image. When the light is poor, turn on the infrared light, remove the infrared filter inside the IR-CUT, and let the infrared component enter to improve the low-noise effect of the image. [0003] However, because the IR-CUT is usually driven by a magnetic valve or a motor, it not only increases the cost of the camera, but also its stability and reliability will gradually deteriorate with the increase of the number of uses, and it often occurs that it cannot be switched during night and...

AI Technical Summary

Problems solved by technology

But only using this filter, when there is sufficient sunlight outdoors, the intensity of infrared light is high, and the 840-860nm light that is allowed to pass through the filter is still causing the infrared sensing unit (IR component) in the imaging chip to generate If the signal is very strong, then in the daytime, when outdoors, the strong signal of the IR component will still have a very large impact on the image signal processing of the image captured by the camera, causing the image to be seriously reddish

In addition, the filter film used in this patent not only has a large number of film layers and complex processing technology, but also uses commonly used high-refractive index dielectric material TiO2 (n=2.35550nm) and low-refractive index dielectric material SiO2 (n=1.45550nm). Dual-purpose bandpass filter, TiO2 material is prone to oxygen loss during evaporation and deposition, forming other low-valent oxide films, resulting in increased absorption, and long-term exposure of TiO2 films to ultraviolet light will lead to increased short-wave absorption of less than 450nm , which will inevitably affect the long-term performance of the filter

[0007] To sum up, except for the IR-CUT technology, none of the above two existing technical solutions can solve the problem of reddish image captured by the camera.

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