CHECK THE CONTRAST
Appropriate lighting is needed if the features are to be visible at all. It is important to create sufficient contrast between the background and the features of the adhesive bead to be inspected, otherwise no algorithm in the world could detect or inspect anything. All image processing systems stand or fall by the contrast. Note that the effect of extraneous light should not be underestimated. The poorer the lighting, the greater the impact of extraneous light.
There are many ways to improve the contrast, including spectral selection, the use of complementary colors, polarization or fluorescence (UV excitation). Laser light section processes in 2.5 or 3D heat pulse processes such as NIR and IR are more complex. All methods aim to create the best possible contrast for the detection of the desired features. No matter which method you use, it is essential that you carefully select the right lighting in advance and that your hardware is set up accordingly.
Don't worry, there are experts on hand who will be happy to help you get the best possible contrast for your dispensing bead. Take their advice – it will make all the difference.