What are the influencing factors of machine vision lens imaging

In recent years, machine vision has been favored by many industries in industrial production and scientific research due to its advantages in performance and imaging. The clear and accurate imaging effect of machine vision is naturally inseparable from the imaging technology of industrial lenses. It is understood that the factors that affect the imaging effect of the lens include several main parameters such as lens, aperture, depth of field, etc. At present, the two major technical indicators that have attracted more attention are basically aspheric lenses and large depth of field. The following will focus on the analysis of these two technologies. The impact of indicators on the imaging effect of machine vision lenses. 1. Aspheric lens technical indicators For the lens, the clarity of the entire picture is an important indicator, and the emphasis here is on the entire picture. Lens lenses generally have two types: spherical and aspherical. Spherical lenses have inherent spherical aberration, astigmatism, and curvature of field, which make the sharpness of the picture low, especially at the edges of the picture, even blurring and other problems. In contrast, aspheric lenses improve the picture limitations inherent in spherical lenses, effectively improve the definition of the edges of the picture, and largely avoid the occurrence of phase difference blur. The clear imaging effect of the aspheric lens is understandable, but its cost is relatively high, and this is the main reason why the aspheric lens has not yet reached the level of popularization in industrial applications. However, due to the use of aspheric lenses to obtain a good image, many customers are still using them, and the aspheric lens market is still an important technical indicator that affects the imaging effect of the lens. 2. Large depth of field technical indicators Depth of field refers to the range of distance that the camera can clearly image. In other words, if you want to get a clear picture, you need the lens to have a good depth of field. The larger the depth of field, the larger the clear range of the picture. After the image is enlarged, the far-end scene You can still see clearly. The large depth of field of the lens can enhance the clarity of the picture and increase the clear area of ​​the picture, which is a major technical indicator that can affect the imaging effect of the lens. Then, when we choose a lens with a large depth of field, we can compare the sharpness of the image after imaging. The depth of field is not an independent parameter, it has a certain relationship with the focal length, aperture, shooting distance and other parameters. For example: the aperture is inversely proportional to the depth of field, the aperture is large, the depth of field is small; the aperture is small, the depth of field is large. The focal length is also inversely proportional to the depth of field. The focal length of the lens is long and the depth of field is small; the focal length of the lens is short and the depth of field is large. The shooting distance is directly proportional to the depth of field. The shooting distance is far, the depth of field is large; the shooting distance is close, the depth of field is small. Three, other technical indicators In addition to the above two technical indicators, there are also some factors that also affect the imaging technology of the lens. For example, a large aperture has a great influence on the contrast of the picture. In dim light conditions, if the aperture is not large enough, the picture will appear dim, the noise will increase, and the picture quality will be greatly reduced.