Why is machine vision light sources important? Light source is the most important factor determining the image quality of machine vision systems. Choosing a suitable light source can achieve optimal separation of target features and background information in the image, greatly reducing the difficulty of image processing and improving the stability and reliability of the system. There are three steps to selecting machine vision light sources:

1. Determine the irradiation method (specular reflection, diffuse reflection, transmitted light, etc.)

Observe the characteristics of the tested area (damage, shape, presence, etc.). Observe the surface (plane, surface, and whether there are uneven bumps) to determine.

(1) Specular reflection type:

The light received by the lens is specular reflection light from the subject being photographed

(2) Diffuse reflection type:

Avoid specular reflection from the subject and receive overall and uniform light

(3) Transmission type:

Receive light from the background of the subject being photographed. It is a lighting method for detecting contours.

2. Determine lighting mode and shape

Determine based on workpiece conditions, setting conditions, etc. Circular light, low angle light, coaxial light, cover light, etc.

After selecting lighting methods such as specular reflection, diffuse reflection, or transmission, the lighting type is determined based on the detection purpose, background, surrounding environment, etc. Generally speaking, mirror reflection can choose coaxial incident lighting, circular lighting, or rod lighting, diffuse reflection can choose low angle lighting, circular lighting, or rod lighting, and transmission can choose surface lighting or rod lighting. The setting distance of circular lighting and bar lighting is more flexible, therefore the application range is wider.

3. Determine the color (wavelength) of light

Determine based on the material, color, etc. of the workpiece and background. Blue, red, white, etc. When using color cameras, white light is generally used. If using a black and white camera, attention should be paid to using complementary colors, wavelength, and detection.