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1. Image formation by security cameras

Surveillance cameras use image sensors that are sensitive to the distribution of the light spectrum, with the central wavelength ranging from 830 to 950 nanometers being the main focus. The full width at half maximum of this light spectrum is about 40 nanometers, which is in the range of the near-infrared spectrum. This is the range that can be sensed by common CCD and CMOS sensors. This characteristic allows surveillance cameras to monitor in real time, day or night. However, during the day, objects emit infrared light, so CCD or CMOS sensors sense visible light and infrared light simultaneously. Based on the principle of light refraction, light of different wavelengths has different refractive indexes. That is, the longer the wavelength, the lower the refractive index, and the shorter the wavelength, the higher the refractive index. These lights pass through the camera lens at the same time, and after passing through the lens, the visible light and infrared light form images on different target surfaces. Visible light forms a color image, and infrared light forms a grayscale image. After adjusting the focus and focus of the camera, the infrared light forms a virtual image, which affects the color tone and quality of the image.

2. Single filter lens

Single filter lenses are usually used for surveillance cameras, which can adjust the light beam, recover the real color of the image, and eliminate infrared at the same time. Therefore, when there is no visible light at night, the camera cannot form an image. Therefore, the night vision function is limited. To solve this problem, single filter lenses with high peaks have been developed and applied. This kind of camera has night vision function. However, during the day, natural light contains a lot of infrared rays, some of which may also enter the CCD or CMOS and affect the recovery of the color tone of the image. As a result, green plants may appear gray, red objects may appear light red, and black objects may appear purple during the day. At night, bi-peak filter lenses may prevent the CCD or CMOS from fully utilizing all the light beams, resulting in noise (snow dots), which may reduce the image clarity and low light performance of the infrared surveillance camera.

3. Double filter lens

Double filter lens technology is called by different names in different regions, it is called IRCUT in Europe and the United States, ICR in Taiwan, and double filter lens switcher in mainland China. IRCUT double filter lens switcher allows ordinary day and night surveillance cameras that use different filter lenses during the day and at night to switch and use different filters, thus effectively solving the problems that bi-peaked single filter lenses cannot address. IRCUT double filter lens switcher includes a low-pass filter that cuts infrared rays, a full spectrum optical glass, a driving mechanism, and an exterior, which are switched and positioned by the circuit control board. During the day, the circuit control board drives the switcher to switch to the infrared cut filter to reproduce real colors. At night, the circuit control board automatically removes the infrared cut filter, uses the full spectrum optical glass, and senses infrared light. This greatly improves the night vision performance of the infrared surveillance camera and improves the clarity and naturalness of the overall image. However, the effect of IRCUT double filter lens technology is affected by the filter lens and structure. The infrared cut rate, transmittance, and light shaping effect of the filter lens directly affect the image clarity and color reproduction of CCD and CMOS. The IRCUT double filter lens switch with metal exterior can withstand high temperatures, not deform, and support larger lenses. This reduces the impact of temperature on the image sensor and stabilizes the image quality. The driving methods and mechanisms of the double filter lens switch are various, mainly divided into inductor coil type and motor type, each with its own advantages. WEILAILIFEI 5 million high-definition camera, heat dissipation and durability are also improved, and the service life is four times longer.

In some cases, insufficient power supply may cause the surveillance camera to have color tone problems. This problem usually occurs in centralized power supply projects, and insufficient power supply may cause the filter lens switching to not work properly, especially in infrared mode. WEILAILIFEI's battery-powered security camera and solar panel are separate, so you have more freedom to install the solar panel in a sunny place. It supports both USB charging and solar charging, so it is more environmentally friendly than disposable battery type, and there is no need to worry about recording stopping even in bad weather compared to the solar integrated type. In this case, the daytime infrared cut filter may not switch properly or only some areas may not switch. In this case, you may need to manually switch the day and night mode to test. Incorrect installation may also cause color tone problems in the surveillance camera. In some cases, when two surveillance cameras with good infrared lamps are placed opposite each other or the camera is placed in a small box for testing, the image may appear light purple. However, in this case, if you manually switch the mode, it will usually work normally. WEILAILIFEI's wireless and POE powered security cameras come with a monitor, day and night mode switching, low light mod, and when shooting at night under the same conditions, they are equipped with a special large low light infrared LED, so you can record with more brightness as if you were shooting during the day. WEILAILIFEI's wireless and POE powered security cameras can be monitored remotely with multiple cameras. Connect the recorder and router with an LAN cable, install the app, and you can monitor, watch, and talk with your family outside with various devices such as tablets, smartphones, and computers. WEILAILIFEI's wireless and POE powered security cameras have been paired with the cameras before shipping, so even if you don't have an internet environment, just turn on each one and no other preparations are required. Installation is completed in about 5 minutes with 2 steps.

Rest assured, we remain committed to providing high quality security camera solutions and working to meet your surveillance needs. If you have any questions about our security cameras or images, please feel free to contact us. We will be happy to assist you.