The Connection Between the Machine Vision System and the Light Source and the Judgment of the Quality of the Light Source

Ⅰ. The connection between machine vision system and light source

The light source is one of the important components in the machine vision system. A suitable light source is a necessary condition for the normal operation of the machine vision system. Therefore, the selection of the light source of the machine vision system is very important.

The purpose of using the light source is to separate the object to be measured from the background as clearly as possible to obtain a high-quality, high-contrast image; to "freeze" the moving target on the image; to enhance the marginal clarity of the target to be measured; to eliminate shadows;

The machine vision has three major skills, namely imaging skills, processing skills, and motion control skills. The imaging skills are inseparable from the light source. The selection of the light source and its function directly affect the success or failure of the system, as well as the processing accuracy and speed. Therefore, the light source plays an insignificant role in the machine vision system.

When selecting a light source for a machine vision system, it is basically necessary to consider factors such as brightness, position of the light source, surface texture and shape, stability, color, etc. Only when the light source meets the requirements of these elements in production management or quality inspection can clear Image data, as accurate data information for operators to use. Therefore, these elements to be considered when selecting a light source can be said to be the basic elements and the basis for judging whether the light source is available.

However, the variety of light sources in the machine vision system is relatively complicated. In order to achieve a better effect, it is necessary to select suitable varieties in detail on the basis of ensuring availability. 

Ⅱ. The machine vision system can judge the quality of the light source through the following elements:

1. Contrast

The important task of lighting used in machine vision is to create a large contrast between the features that need to be investigated and the image features that need to be ignored, so that the features can be easily distinguished. Contrast is defined as a sufficient grayscale difference between a feature and its surrounding area. Good vision lens optic should ensure that features that need to be detected stand out from the rest of the scene.

2. Brightness

The brightness of the light source is not enough, it is necessary to increase the aperture, and then reduce the depth of field.

3. Uniformity

The light source with good uniformity makes the system work stably.

4. Maintainability

It mainly means that the light source is easy to install and easy to replace.

5. Useful cycle

The brightness of the light source should not decay too quickly, which will affect the stability of the machine vision system and increase the cost of maintenance. The brightness of the lamp with high calorific value decays quickly, and the life of the light source will also be greatly affected.