Hobby photographers are familiar with how tricky correct illumination can be. Dull contrasts and fuzzy contours can kill even the most beautiful photograph. However, the consequences for industrial image processing weigh much heavier. If visual quality assurance breaks down, this can result in costly consequences. The objective of industrial image processing is to use appropriate lighting systems to contrast the products that need to be inspected, so that all of the relevant details and deviations can be detected by the camera. SCHOTT ranks among the global leaders in technology when it comes to this highly specialized market. Electronics manufacturers, the pharmaceutical industry and subcontractors to the automotive industry all rely on lighting systems from SCHOTT. ”This is a very attractive market with annual growth rates of around 25 percent. The worldwide sales volume for this type of lighting technology alone reached 320 million euros in 2005,” explains Jürgen Schumann, head of the industrial product group at SCHOTT Fiber Optics.
Illumination technologies
What light is the right light?
For the most part, the type of lighting is determined by the characteristics of the material that objects are made of and the lighting technique that is used. Here, factors, such as light delivery to the object and light intensity are crucial. Generally speaking, the higher the level of brightness, the quicker the inspection cycles. This increases throughput and reduces the costs per unit.
With lesser demands on lighting, even simple halogen spotlights, light bulbs or LED arrays without electronic excitation often suffice. These light sources are inexpensive and allow for a uniform illumination.
Fluorescent tubes provide diffuse light. The advantages of fluorescent lighting lie in their high life spans of around 15,000 hours and their relatively low initial cost. Fluorescent tubes can be used wherever no special requirements apply to the variability of the lighting. If faster inspection speeds or more complex inspections are required, fiber-optic systems or high quality LED systems are recommended. Fiber optics is known for its particularly high light intensity, flexible component shapes and uniform lighting.
New trend led
A development team at SCHOTT in Mainz is now working to resolve these issues and Jürgen Schumann is optimistic. ”We are confident that we will be successful in getting these technological challenges under control quite soon. After all, we remain committed to retaining our leadership role in this market,” he concludes.
Schott: Placed Into Perspective
Automated optical inspection for quality assurance is now standard in modern manufacturing. Achieving reliable results calls for custom-designed illumination of the objects.