What are the Parameters of Industrial Camera?
Industrial camera is a key component of machine vision system, whose most essential function is to convert optical signals into ordered electrical signals. The industrial camera lens is equivalent to the role of the pinhole in the pinhole imaging.
Choosing the right industrial camera lens is also a key step. Before selection, we should first understand the parameters of industrial camera lenses. In this article, ATO industrial automation will give you a detailed introduction to the parameters of industrial camera.
Focal Length:
Focal length is the distance between the clear image formed from the center of the industrial vision camera to the glue plane. Pay attention to the distinction between the focal length of the camera and the focal length of a single convex lens is two concepts, because the lens installed on the camera is composed of multiple thin convex lenses. The focal length of a single convex lens is the distance between the parallel rays converging to a point and the center of the convex lens. The focal length determines the angle of view. A small focal length and a large angle of view lead to a large range of observation. The focal length is large, the angle of view is small, and the observation range is small.
The focal length parameters of industrial camera lenses are divided by "mm". The conventional ones are 6 mm, 8 mm, 12 mm, 16 mm, 25 mm, 35 mm and 50 mm. Generally, 6 mm lens is within 15m, 8 mm lens is within 20m, the angle of view is about 50 degrees, 12 mm is within 30-40m, about 30 degrees.
lris:
Aperture is a device used to control the light amount of light passing through the lens and entering the photosensitive surface in the body, which is usually in the lens. For the manufactured lens, we can not arbitrarily change the lens lens, but we can control the light amount of the lens by adding polygonal or circular aperture light shed with variable area inside the lens. This device is called aperture.
How does the aperture control the amount of light coming in? We can think of the aperture of a industrial camera as an adult pupil. When the light is intense, the pupil will shrink automatically. When the light gets weak, the pupil dilates, allowing the surrounding retina to image properly.
The same principle applies to the aperture of a industrial smart camera. When the light is low, we increase the aperture to let more light into the camera, and vice versa. In addition to adjusting the amount of light coming in, the aperture has another important function: adjusting the depth of field.
The aperture is represented by F, measured by the ratio of the lens focal length to the aperture D. Each lens is marked with the maximum F value, for example, 8mm/F1.4 means the maximum aperture D is 5.7 mm. The smaller the F value, the larger the aperture, and the larger the F value, the smaller the aperture. Optimum aperture - generally in F/4-F/8.
Depth of Field:
Depth of field refers to the range in which the image is still clear within a certain distance after the object is clearly focused. The depth of field varies with the aperture value of the lens, focal length, shooting distance, the larger the aperture, the smaller the depth of field, the smaller the aperture, the greater the depth of field. The longer the focal length, the smaller the depth of field, and the shorter the focal length, the greater the depth of field. The closer the object is to be photographed, the smaller the depth of field is. The longer the shooting distance is, the greater the depth of field is.
Resolution:
Resolution represents the ability of the lens to record the details of an object. It is measured in the number of black and white pairs that can be resolved per millimeter, "LP / mm". The higher the resolution, the clearer the image. We often say that the display resolution is the precision of the screen image, referring to how many pixels the graph can display.
