Common industrial camera target sizes and corresponding lens selection strategies
Target surface size, that is, the size of the photosensitive part of the image sensor, is an important parameter of industrial cameras. Just like the "field of view window" of the camera, it not only determines the range of pictures that the camera can capture, but is also closely related to the combination of the lens, and jointly affects the imaging effect.Common target surface sizes are 1/4, 1/3, 1/2, 2/3, 1/3, 1/3, 1/3, 1/3, 2/3, 1/3,There are several types, and of course there are other specifications.Cameras with different target surface sizes have their advantages and disadvantages in practical applications.Camera with smaller target surface sizes, such as 1/4 and 1/3, have the advantages of small size and low cost. They are more suitable in some application scenarios with strict space requirements and limited budgets. For example, small security surveillance cameras are installed in narrow corners or equipment with limited space. They can complete basic image acquisition tasks without occupying too much space; however, the size of the small target surface also means that the photosensitive area is relatively small. Under the same lighting conditions, the total amount of light received is less, the image noise is relatively high, and the image quality will be affected to a certain extent, just like looking at the outside world through a small window, the field of view is limited and the picture may not be bright and clear enough.Camera with larger target surface sizes, such as 2/3 and1'', with a large photosensitive area and can receive more light, which makes them better perform in low-light environments. The images they shoot have fewer noise, delicate picture quality, and high color restoration. They are very popular in areas such as professional photography, astronomical observation, and high-end industrial inspection that require strict picture quality.For example, in astrophotography, cameras with large target surface sizes can capture weaker starlight, showing the magnificent details of the vast starry sky; in the appearance inspection of industrial products, tiny flaws and texture changes on the product surface can be clearly presented to ensure that product quality meets high standards.The target surface size has a close relationship with the lens focal length, field of view angle and image clarity.At the same perspective, the larger the target surface size, the longer the focal length. This is like a human eye. The larger the eyeball (equivalent to the larger the target surface size), the longer the distance that can be focused (the longer the focal length), and the larger and clearer the object you see; on the contrary, the smaller the target surface size, the shorter the focal length.In terms of field of view angle, the larger the target surface size, the smaller the field of view angle, and the range of images that can be photographed is relatively narrow, but the image of objects in the center of the picture is larger and clearer, which is suitable for close-up shooting or high-precision detection of specific targets; while the camera with a small target surface size has a larger field of view angle, which can cover a wider scene, and has advantages in monitoring large areas and shooting panoramic images.When selecting the camera, the lens must be selected reasonably based on the target surface size to ensure that the two match each other in order to achieve the best performance.Generally speaking, the imaging diameter of the lens must be able to cover the camera's target surface size, otherwise there will be problems such as viscera or the inability to fully image.If the camera's target surface is large, you need to choose a large-diameter and long-focus lens that is suitable for it to make full use of the photosensitive area of the target surface and obtain high-quality images; for cameras with small-target surface sizes, choosing a short-focus and small-diameter lens can not only meet the imaging needs, but also control costs and volume.For example, in the security monitoring system, for scenes that monitor long-distance targets and have high image quality requirements, a 1-target-size camera is usually used with a telephoto lens to achieve accurate monitoring of the target; for monitoring in small indoor stores, 1/3 of the target-size cameras can monitor the target in all aspects with a wide angle lens.
