Bubble-X securely identifies air bubbles

When liquids are inspected during pharmaceutical production, it sometimes happens that camera systems consider flawless products to be defective. The cause is often harmless air bubbles mistakenly registered as particles. The Seidenader Bubble-X inspection technology from Körber uses refraction effects to clearly identify such objects and thereby reduce the false reject rate by up to 50 percent. 

It’s often the small things that make a big difference. This is particularly true in pharmaceutical production. For example, if a particle is discovered during the inspection of a liquid, whether in a syringe, ampoule, or another glass container, the inspection system has fractions of seconds to decide if the product is safe or not. “As a precautionary measure, such products are declared to be rejects even though they might actually be in flawless condition,” says Werner Halbinger, image-processing and laboratory engineer at the Inspections unit of Körber Business Area Pharma. This problem is prevalent in the biopharmaceutical industry. Why is that? The protein-based nature of these pharmaceuticals makes them prone to the creation of air bubbles, which many camera systems mistakenly consider to be dangerous glass particles resulting in the rejection of the product. Because such products cost up to €500 per unit to manufacture, such false interpretations can rapidly become very expensive. “A reliable inspection solution with a low false reject rate (FRR) thus helps companies save a lot of money,” says Halbinger. That’s why Halbinger and his team developed Bubble-X, a technology that reliably inspects sensitive liquids at high speeds commonly used in pharmaceutical production.

Viewed in the right light 

Conventional solutions for distinguishing air bubbles from foreign objects in liquids are generally complex and make inspections take longer. Waiting for particles and air bubbles to distinguish themselves takes far too long to be suitable for high-speed inspection. “By contrast, Bubble-X uses the speed of light, or, more precisely, the effects of the refraction of light,” says Halbinger. It employs a spectral-coded illumination system that consists of three colored light sources: red, green and blue. The rays of light pass through the liquid in the individual containers. A special arrangement of lenses guides the light to pass through the liquid unhindered, allowing only the green rays of light to hit the detector in the color camera behind the container while the other colors of light go past it. 

Color patterns help distinguish objects 

However, if the rays encounter air bubbles or particles as they travel through the liquid, one of three things will happen. A normal, opaque particle blocks the light and appears in the camera image as a dark object in front of a green background. By contrast, transparent particles such as glass particles and air bubbles refract the light and redirect it in different ways. “Because of the laws of refraction, transparent particles cause not only the rays of green light but also those of blue and red light to hit the detector, where they create a specific color pattern,” says Halbinger. “An air bubble does the same, except that air refracts light differently than glass, for example, and causes the color pattern to reverse.” This physical effect enables Bubble-X to distinguish between the two objects -and it does this within fractions of a second.

Saving millions of euros with Bubble-X 

This spectral-coded illumination can cut the false reject rate during inspections by half. Whereas conventional inspection systems have an average false reject rate of two percent, Seidenader Bubble-X reduces this rate to one percent. Although this reduction may seem unspectacular at first glance, it quickly adds up. “A pharmaceutical company that produces one million units per year worth €500 each can save up to five million euros if the FRR is cut in half,” says Halbinger.

Even more efficient thanks to deep learning

Bubble-X reduces the false reject rate by as much as 50 percent. In combination with the new deep learning software Seidenader Eject-X from Körber, it can decrease the number of mistakes even more. The software solution uses artificial intelligence to analyze images of production defects. “In doing so, Eject-X trains an algorithm that makes the image-processing software of inspection cameras even more reliable. As a result, companies can improve specific stations of their inspection machines,” says Halbinger.

Inspection solutions from the market leader 

At the Körber Business Area Pharma, the Inspections unit has been developing solutions for the pharmaceutical and biotech industries for over 125 years — and it’s the global market leader in this field. Its portfolio includes automatic inspection machines as well as semi-automatic systems, inspection applications for in-process control, and inspection equipment for laboratories and product development. Depending on customer requirements, various technologies can be combined in the fully automatic systems for high-performance inspections. In addition to camera-based solutions such as Seidenader Bubble-X or a 3D inspection system for highly viscous products, the unit also offers technologies for high-voltage leak detection or laser-based head-space analysis. The machines are tailored specifically to the containers and products of the pharmaceutical and biotech industries. The machines also provide companies with the required level of flexibility: The machines’ modular arrangement enables them to be adapted and expanded to change production conditions at any time. As a result, pharmaceutical and biotech companies can ensure both the safety of their products and the future-proof quality of their manufacturing operations. 

Körber – delivering the difference in pharma