Interview: Optical inspection scanner systems are faster, more accurate and more economic than camera based solutions.

12 October 2011 - Gerald Landt is the director of the German AOI supplier modus high-tech electronics GmbH. The company develops, manufactures and sells automatic optical test and inspection systems (AOI) for production control. Contrary to most other providers, who use moving camera systems, modus uses static full scale image scanners.

AaT: There are about more than 50 providers of AOI-systems (automatic optical inspection) for the German-speaking area. How can modus high-tech electronics, which is a comparatively small company, prevail in this market?

Gerald Landt: Since more than a decade our company is considered a specialist for industrial image process systems and we provide scanner based products that reliably inspect the quality of electronic modules in a very short time. Like our competitors, we concentrate on specific inspection areas, e.g. on Printed Circuit Boards. For this purpose we developed an own scanner technology. Because of the continuous enhancements of our scanner systems, we gained a significant unique feature in that area of the market.

AaT: With this kind of multifaceted range on the market, it surely has to be very difficult for an electronics manufacturer to find the right solution for specific application. What should be looked out for when purchasing such a system? Which areas do your systems cover?

Gerald Landt: Before purchasing an AOI-system it is advisable, for an optimal solution, that the user clearly describes the inspection assignment, e.g. paste, chip or soldering control, and his expectations in form of a performance specification. When the user’s expectations of the system and the, for him, relevant criteria are not defined it can lead to unpleasant surprises, because the challenge lies in the details.

In general our systems are capable to inspect all manufacturing steps, i.e. paste control after printing, chip control previous to the soldering furnace as well as soldering control in the End of Line Test. In addition we offer AOI-systems in the „One Piece Flow“ area, which are based on matrix cameras and can be adjusted customer-specific. The application areas amongst others are welding and bonding control. Special applications like „Conformal Coating“ Test with UV-illumination as well as „Stencil” tester and mechanic surface control complete our portfolio.

AaT: Contrary to many other providers, you focus mainly on scanner solutions. What kind of advantages do these systems have compared to camera systems?

Gerald Landt: Each image detection system, depending on the application area, has certain advantages for the user. A huge advantage of the scanner systems is the velocity: the image detection takes place in one scan and the image data is processed in maximum 25 seconds. Scanner areas of 300 x 400 mm (A3) as well as 420 x 550 mm (A2) are possible. Scanner systems provide a significantly higher image resolution than camera systems. The image processing takes place with True Color RGB 24-Bit, with an entire bitmap with ca. 820 M pixel memory. Contrary to the bigger part of the competition, modus uses the original image data in bitmap format, instead of the virtually processed images, whereby a higher image resolution is possible. Above and below ground level working processes are simultaneously possible, which shows another time saving. The specific feature of modus-AOI-systems is that, thanks to parallax free image detection, the scanner systems provide a reflected image – i.e. an image free of perspective distortions. A special Multi-LED-illumination system is, adjusted for the image detection, switchable between white or red illumination. Another important advantage is the vibration-free working process, which is cost saving because the equipment doesn’t have to calibrate itself each time it is used as well as the minor maintenance requirements. Solely the glass plate has to be cleaned when dirty, here as well you can see the cost saving.

AaT: A lot of electronic manufacturers have production sites aboard. In which countries is your business active, beyond the German-speaking area? How do you ensure an all-embracing support for the users aboard?

Gerald Landt: Our distribution and service partners, e.g. Accelonix and Itochu, represent us in a lot of countries in Europe, Asia and America. To some extent we have long business relationships with these companies; therefore we have experienced co-workers to ensure an all-embracing support for our customers.

AaT: How do you see the future for the AOI-market? Will there be as many providers in five years? Where does it go – considering the technological advances?

Gerald Landt: Of course you can only speculate when talking of the prospective development of the market. Personally, I see an increasing demand of AOI-systems in Germany and Western Europe, because efficiency and quality control of the production is a mayor part to optimize and reduce the costs.

The specialization in the niche market will gain importance, as long as the variety of applications in the specific inspection areas continues. Because of consolidation and synergistic effects there surely will be movement in the market shares.

In the coming years CCD-sensors with ever higher amounts of pixels and speed will come on the market. On the fist look this may be an advantage, but the resolution of the object lens strikes more and more against the technical possibilities in the accepted budged. An optical system is only as good as its weakest link. Therefore I think that the optical systems are still an essential quality feature for an AOI. The image quality depends on the optical characteristics. This is very important in the AOI area, therefore very important to modus, because the image quality for the control of high quality manufacturing processes matter a great deal.

AaT: Thank you very much for the interview!

The interview was held by Herbert Hönle