Optimised automated detection of UDI codes
17 Aug 2015
The UDI system for unified product labelling of medical products has been developed in the USA and will become mandatory in Europe as well. The current version of the Medical Device Regulation (MRD) has been revised to include this obligation. UDI labelling in medical technology will become mandatory in the United States in multiple phases from 2014 to 2020 in accordance with the risk factor of the relevant product. Labelling of the highest risk class medical products came into force at the end of 2014 and will eventually be implemented worldwide. Affected products and their packaging must now contain the UDI code. Class III medical devices for example have had to comply with this regulation since September 2014. From September 2015 onwards the UDI regulation will also apply to life-supporting and life-sustaining implants. Starting in September 2016 all Class II medical devices will be affected, and from September 2018 onwards the regulation will be expanded to Class I medical devices. Due to this schedule UDI regulation has become a frequently discussed topic in businesses in the medical technology industry.
UDI offers a range of benefits for manufacturers, prescribers of medical products and of course patients. Manufacturers of medical technology products use the code for error-free and quick detection during manufacturing, in the warehouse, in commissioning and for shipment. Barcodes have proven themselves manifold in the logistics industry. UDI enables traceability of locations, shipments and workflows in processes. Manual entries can be avoided, processes can be automated and properly documented.
The recipient uses the code for goods receipt, in-process inventory and consumption recording. In the end, UDI enhances patient safety by ensuring full traceability of medical products at any time. The identification of unique codes in a database furthermore prevents product counterfeiting and piracy. Copies of inferior quality can be identified more quickly – a major bonus for the health of patients.
A wide range of UDI applications
There are many different types of products which must be labelled with a UDI code. The list includes packaging for medicine and medical tools, as well as surgical tools such as scalpels, etc. Products that replace body parts, such as prostheses, artificial joints or stents must bear a UDI code or will be required to do so very soon.
The regulation requires the UDI code on the products to be applied as a machine-readable label such as a barcode or plain text. The code is a key for the UDI database (Unique Device Identification Database, UDID) containing product information. This information includes a unique identification of major manufacturers and product data, either printed on the product itself or on the packaging, as well as manufacturer master data in a central database.
UDI is more than a simple product code. It is a system that guarantees full traceability of medical products over the entire supply chain, and it therefore offers major benefits for product recalls and logistics chain optimisation.
Machine vision as the key element
Machine vision systems become more and more important for UDI code identification. Failure-free detection of these labels is a crucial element in the entire UDI supply chain and requires systems that can reliably scan every single code, even at high speeds.
This is a complex task bearing in mind all the different materials and colours being used for code printing. Metal products such as artificial joints are a major challenge: when scanning the code the light is reflected from the surface, making reliable code detection extremely hard to accomplish.
New lighting solution for reliable code identification
The Japanese manufacturer CCS is one of the world-leading suppliers of LED lights for industrial machine vision systems. The company's newest development offers an innovative technological approach for dealing with reflections from metallic and other surfaces during code identification.
The new dome-shaped illumination – an enhanced version of the current PDM series – makes it possible to deal with this issue. All products in this series offer a combination of diffuse, coaxial and low-angle illumination for a fully shadeless and uniform diffuse illumination of the object. A uniform illumination is only made possible by combining these three illumination methods with their distinctive benefits: diffuse dome illumination offers a shadeless illumination of the object, coaxial illumination is particularly suitable to eliminate possible shadow formation by the camera opening in the dome, and the low-angle light in the PDM series is ideal for highlighting structures such as needled codes or even scratches, cracks or dents.
In the standard version the PDM lights are available with red, blue and green LEDs, perfectly suited for inspection of reflective or uneven surfaces, for identification of foreign objects and for character and text recognition. Here is one example for the benefits of PDM technology: reliably scanning contact lens packaging using ordinary ring illumination is very difficult to achieve due to the reflective and uneven surface of the packaging foil that bears the code. Using PDM lighting results in a clear and easy to process image.
The latest user configurable addition to the PDM series is the CCS PDM-150-15 FC which can be controlled via 7 independent channels. Three channels each for red, green and blue in the coaxial and dome lighting, and one additional channel for the dark field ring light. The latter is available to order in red, green, blue or white. This allows for individual adaptation and optimisation of the illumination towards the objects the UDI code shall be scanned from – a prerequisite for the highest reliability in UDI code scanning.
When scanning contact lens packaging (left image) a conventional ring light (centre image) may not be able to reliably scan the code from the reflective and warped surface. Using PDM lighting however provides a clear and easy to process image (right image).
A complete machine vision solution
STEMMER IMAGING is the distributor for CCS LED lightings in Germany, Austria and further European countries. The German company with its headquarters located in Puchheim near Munich is Europe's largest technology distributor for machine vision and offers its clients a comprehensive product and service range that includes all the elements required to plan and execute machine vision systems.
Scanning UDI codes is a typical machine vision task : it is basically reading barcodes, but under more demanding conditions – i.e. on a small scale and on reflective materials – and with the more stringent safety requirements of a medical application. Not only suitable illumination, but high quality optics and camera systems as well as reliable software and hardware components are essential elements in this type of application. STEMMER IMAGING is able to cover all these requirements through cooperation with various international suppliers of machine vision components. Their tailored services such as feasibility studies, training, support, etc. help medical technology system builders to meet their individual demands.