What is IR infrared lens

The IR lens is an infrared lens. It uses a special optical glass material and uses the latest optical design method to eliminate the focal plane shift of visible light and infrared light, so the light from the visible light to the infrared region can be in the same focal plane. imaging, so that the image can be clear. In addition, the IR infrared lens also adopts a special multi-layer coating technology to increase the transmittance of infrared light, so the camera with the IR lens can monitor the distance farther at night than the camera with the ordinary lens, and the effect is better.

The difference between IR lens and ordinary lens:

1. When the ordinary lens uses infrared light at night, the focus position will change. Makes the image blurry and needs to be adjusted to make it clear. The focal point of an IR lens is the same in both infrared and visible light. There are also called parfocal lenses.

2. Because it is used at night, the aperture should be larger than that of ordinary lenses. The aperture is called the relative aperture, which is represented by F, which is usually said to be a large f, which represents the relationship between the effective diameter of the lens and the focal length. The smaller the value, the better the effect. The greater the difficulty, the higher the price.

IR lens is an infrared lens, mainly used for night vision, most used in surveillance cameras.

After the ordinary CCTV lens is accurately focused during the day, it will have a focus shift at night, and it has to be repeatedly focused during the day and night! The IR lens uses special optical materials, and multi-layer coating is applied to each lens unit to maximize the impact of day and night light changes. No need for repeated adjustments

IR lens is also another important development area of imported lens products in recent years, which is to meet the market's 24-hour monitoring needs. With the increasing complexity of social security, people not only require cameras to be able to complete surveillance tasks during the day, but also to be responsible for the security work at night, so the application of day and night cameras will become more and more popular, and the IR lens is a good helper for day and night cameras. .

At present, China's day and night camera products mainly realize day and night conversion through infrared filters, that is, open the filter during the day to block infrared rays from entering the CCD, so that the CCD can only sense visible light; in the night vision state, the filter stops working , no longer block infrared rays from entering the CCD, and the infrared rays are reflected by the object and enter the lens for imaging. However, in practice, the picture is often clear during the day, but the picture becomes blurry under the condition of infrared light.

This is because the wavelengths of visible light and infrared light (IR light) are different, and the different wavelengths will lead to different positions of the focal planes of the imaging, resulting in virtual focus and blurred images. The IR lens can correct spherical aberration, so that different light can be focused on the same focal plane position, so that the picture becomes clearer and meets the needs of night monitoring.