When an engineer begins the process of specifying a new machine vision system, they will often think very carefully about the line speed, the optics, and the image processing software. Lighting is often the next consideration because appropriate lighting can significantly reduce software development time and can even be critical to the success or failure of the project. The aim of the lighting will be to project a uniform area of light over the field of view so that a sharp image is obtained and the desired feature can be separated from the background, regardless of any ambient light that may be present. Lighting may have other goals, for example to minimize the effects of motion by strobing the light, or in a more complex implementation lighting may be used to combine data from different lighting schemes.
The lighting controller is frequently only considered towards the end of the project. Frequently, a dedicated machine vision equipment supplier will remind the customer about the lighting controller in a vital “do you want fries with that?” moment. However, the lighting controller is far more than an accompaniment to the main dish. Machine vision experts have learned that a great image is essential for reliable machine vision systems because no amount of software processing can recreate data that is absent at the image sensor. Getting that great image, time after time, needs consistent illumination and accurate, dependable control of that lighting. Lighting equipment vendors will willingly provide consultation on how to properly light an inspection scene and a good one will also understand the different types of lighting controller and be able to guide you to the best choice for your particular application.