Vision inspection is the most common method for quality control operations to check form, fill and labelling. Vision is not without its challenges, and the selection of lighting and lenses is critical to reliable fault detection and low false-reject rates.
We have extensive experience with everything from simple ‘smart sensors’ and ‘smart cameras’ up to the highest resolution systems with line scan cameras, telecentric lenses and collumated lighting and PC based vision software.
Like most things in automation, it is a process of understanding the exact needs then selecting the optimal solution, almost always with tests and trials to find the best solution. We often work with key vendors and vision experts to assemble a system perfect for your needs.
Each vision project will require a specific configuration of lighting, lens, camera and software to deliver an optimal solution. The system will only be as good as the weakest link so it is essential all these elements are designed and selected to work together in harmony.
Optimal lighting is probably the most important and often challenging aspect of a vision system. You must ensure ambient lighting is overpowered (or reduced) while considering back-light versus front light, collimation or dispersion and polarisation – all to achieve the optimal view of the features critical to your inspection.
Strength, timing and strobing is also critical to both capturing the requried image and also avoiding motion blur.
Getting the perfect view of your product is obviously critical to the process. There are a miriad of lenses that can view out, along, in and around your product. Depth of field, resolution, field of view all must combine to ensure the resultant image clearly presents the critical features.
Some lenses can give you a 360° view either inside or around a product. Telecentric lenses ensure an undistorted ‘parallel’ view. And then there is just ‘smoke and mirrors’ to get different views and angles.
To ensure you ‘got the shot’ the camera selection is critical. You want to ensure sufficent resolution to capture the detail needed without over-burdening the processing with too high resolution. The choise of colour or monochrome is also required.
Depending on the rate of inspection and speed of the product the camera performance for exposure, data transfer and frame rate will also be important.
The smart work of a vision system is in the software. Simple tasks can be programmed into a ‘smart camera’ while more complex tasks require a dedicated computer to achieve the inspection in the time available.
We have experience with all the leading vision processing software to program the task, or we can also apply the latest ‘Deep Learning’ or Artificail Intelligence’ system to train the system.