In machine vision system, it is very important to obtain a high-quality image that can be processed. The reason why the system is successful is to ensure good image quality and obvious features. The failure of a machine vision project is mostly caused by poor image quality and unclear features. To ensure a good image, you must choose a suitable light source.

Basic elements of light source selection:

Contrast: Contrast is very important for machine vision. The most important task of lighting in machine vision applications is to maximize the contrast between the features to be observed and the image features to be ignored, so as to facilitate the distinction of features. Contrast is defined as having sufficient gray scale difference between the feature and its surrounding area. Good lighting should ensure that the features to be detected stand out from other backgrounds.

Brightness: When selecting two light sources, the best choice is to choose the brighter one. When the light source is not bright enough, three bad situations may occur. First, the signal to noise ratio of the camera is not enough; Because the brightness of the light source is not enough, the contrast of the image is not enough, and the possibility of noise on the image is also increased. Secondly, the brightness of the light source is not enough, so the aperture must be increased, thus reducing the depth of field. In addition, when the brightness of the light source is not enough, random light such as natural light will have the greatest impact on the system.

Robustness: Another way to test the light source is to see whether the light source is the least sensitive to the position of the component. When the light source is placed in different areas or angles of the camera's field of view, the resulting image should not change. The light source with strong directionality increases the possibility of specular reflection on the highlighted area, which is not conducive to the subsequent feature extraction.

A good light source should be able to make the features you need to look for very obvious. In addition to the parts that can be photographed by the camera, a good light source should be able to produce the maximum contrast, sufficient brightness and insensitive to the position changes of the parts. With the light source selected, the rest of the work will be much easier. The specific light source selection method depends on the practical experience of the test.

In machine vision system, it is very important to obtain a high-quality image that can be processed. The reason why the system is successful is to ensure good image quality and obvious features. The failure of a machine vision project is mostly caused by poor image quality and unclear features. To ensure a good image, you must choose a suitable light source.

Basic elements of light source selection:

Contrast: Contrast is very important for machine vision. The most important task of lighting in machine vision applications is to maximize the contrast between the features to be observed and the image features to be ignored, so as to facilitate the distinction of features. Contrast is defined as having sufficient gray scale difference between the feature and its surrounding area. Good lighting should ensure that the features to be detected stand out from other backgrounds.

Brightness: When selecting two light sources, the best choice is to choose the brighter one. When the light source is not bright enough, three bad situations may occur. First, the signal to noise ratio of the camera is not enough; Because the brightness of the light source is not enough, the contrast of the image is not enough, and the possibility of noise on the image is also increased. Secondly, the brightness of the light source is not enough, so the aperture must be increased, thus reducing the depth of field. In addition, when the brightness of the light source is not enough, random light such as natural light will have the greatest impact on the system.

Robustness: Another way to test the light source is to see whether the light source is the least sensitive to the position of the component. When the light source is placed in different areas or angles of the camera's field of view, the resulting image should not change. The light source with strong directionality increases the possibility of specular reflection on the highlighted area, which is not conducive to the subsequent feature extraction.

A good light source should be able to make the features you need to look for very obvious. In addition to the parts that can be photographed by the camera, a good light source should be able to produce the maximum contrast, sufficient brightness and insensitive to the position changes of the parts. With the light source selected, the rest of the work will be much easier. The specific light source selection method depends on the practical experience of the test.