Two core technologies that interfere with lens imaging

The lens is a core device of the imaging effect of a camera device. The quality of a lens imaging effect directly affects the quality of a camera. So, what are the two core technologies that interfere with lens imaging?

I. Depth of Field

   Large depth-of-field lenses have certain advantages in terms of the depth of the picture and capture of moving pictures. Some people on the market have proposed the concept of panoramic depth of the lens, which has certain effects, but it is still limited to the design of fixed-focus lenses. Zoom lenses This is still not possible.

   The so-called depth of field means that a high-definition camera must obtain a very clear picture during monitoring, and the entire picture can be clearly displayed. Even after zooming in, the far-end scene can be clearly seen. At this time, the lens needs a good depth of field. The larger the depth of field, the larger the distance range that can be clearly seen on the imaged image. After the image screenshot is enlarged, the far-end scenes can be seen more clearly, such as in road monitoring. You can see the license plate number and so on after zooming in through the screenshot. Depth of field is an abstract concept and there is no specific number to quantify. In fact, depth of field is also related to focal length, aperture, and monitoring distance. If the focal length is small, the depth of field is good, the aperture is small, and the depth of field is good. The farther the monitoring distance is, the better the depth of field is. It is mainly based on field debugging. Therefore, only through the imaged image, you can see which lens has a greater depth of field in contrast. At present, there are only one or two manufacturers that can make the depth of field of high-definition lenses better. On the basis of making full use of the large depth of field, and can always maintain the sharpness of the lens during the zoom process. Need to refocus.

Aspheric technology

   For a lens, the sharpness of the picture, especially the sharpness of the edges of the picture, is an important aspect that reflects the advantages and disadvantages of the lens. The main method to improve the picture quality and edge effect of the picture is to use an aspherical lens to solve the inherent inherent of spherical lenses. Spherical aberration, astigmatism, coma, field curvature, and other problems caused by poor definition and edge blur.

   It is reported that aspheric lenses have been adopted by mainstream lens manufacturers, which can effectively improve the sharpness of the periphery of the screen and reduce the size of the lens. In addition, it can also effectively increase the amount of light transmitted at the edge of the lens and correct the aberrations caused by spherical lenses. Blur phenomenon. Most of the manufacturers in the interview said that although most manufacturers are rendering aspherical lenses in their propaganda, they have less practical applications. This is mainly due to the higher cost of aspherical lenses. For example, high-grade glass aspheric lenses use a grinding process on the edge of the glass lens, and the common method is to cover the glass spherical surface to make it aspherical. Both of these aspheric processes must increase costs, especially the former. Therefore, aspheric lenses are rarely seen in batch applications, especially in products with less stringent requirements. However, some manufacturers still say that in the electric zoom megapixel lens, because the lens itself is more expensive and the required effect is relatively high, so aspheric surface is a big selling point, and it is also a necessary technical indicator.

  In addition to the non-mirror lenses and large depth of field specified above, the large aperture has a significant impact on the contrast and sharpness of the picture. The low-light and night-time imaging effects also depend on the large aperture index. The aperture is not large enough. If you do this, the overall picture will be dark, the noise will increase, and the picture quality will drop a lot. SD ultra-low dispersion lenses have a natural advantage in improving the sharpness of the color of the picture. The use of infrared ED lenses has a very important role in improving the day and night imaging effect of high-definition lenses. At present, the mainstream high-definition lens brands have focused on infrared functions. Development. It can achieve clear monitoring under low light and night vision conditions. The high-definition and infrared correspondences strengthen the details of monitoring requirements from space and time, which is exactly the eternal theme pursued by the monitoring industry.

  As we all know, the sharpness effect is an indicator of whether a camera is excellent. For the camera, its "eye"-the effect of the lens is the key to determining the quality of the camera. Therefore, the imaging technical indicators of the lens are particularly important. Therefore, we must pay special attention to the choice of lens.