WHAT'S NEW: SHOWSTOPPERS
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A computer-assisted automated stent inspection system introduced at Hannover Fair 2008 rapidly generates a flat, unrolled view of a stent to detect defects to its structure or surface. |
European Medical Device Manufacturer associate editor Yvonne Klöpping walked the show and discovered the following products in the micro and nanotechnology halls that may be of particular interest to medical device manufacturers.
Optical Stent Inspection System Detects Errors in Less Than 30 Seconds
Even the smallest defect on a stent can be a huge concern for the manufacturer, not to mention the patient who will depend on the life-saving device. Product flaws can reduce its effectiveness and may cause serious complications.
To help manufacturers ensure the integrity of their products, Carinthian Tech Research CTR AG (Villach, Austria; www.ctr.at) has developed a computer-assisted automated stent inspection system. Introduced at this year's Hannover Fair, the equipment uses a high-resolution line-scan camera and automated multi-axe scan mechanics to generate a flat, unrolled view of the stent. The camera captures a detailed image of the entire stent pattern, which is then displayed on a computer monitor. Any structural or surface defects can be detected within a few seconds. “The heart of the system is the camera,” says technical engineer Issa Ibraheem, PhD, Optical Sensors & Imaging, Image Processing Systems. “All errors larger than 200 µ m can be detected immediately.”
The photosensitive device in a conventional area camera is arranged in a matrix such as a square or a rectangle. Hence, it captures a two-dimensional image within one frame in a single exposure and doesn't provide an unrolled view of the stent. The photosensitive device in a line-scan camera, on the other hand, consists of contiguous, precisely mounted elements that are arranged in a linear row. This way, a two-dimensional image can be captured that enables a complete unrolled view of the stent.
Developed mainly for stent manufacturers, the system also can be helpful to cardiologists during presurgery evaluations, notes Ibraheem. “Of course, it is necessary to inspect stents during production,” he says, “but it is also advisable to check a stent for flaws right before surgery.”
The machine can inspect stents up to 20 mm long and in varying diameters. The system features an image size of 6144 x 1740 pixels, a resolution of ±2 µm, ±50 µm depth of focus, and a scanning time of less than 30 seconds.
Microwelding Gets a Boost with Fibre Lasers
Laser-based microwelding has been gaining converts in the medical technology arena, and fibre laser technology is increasingly being used as an alternative to Nd:YAG lasers for applications such as sealing pacemaker cases. Fibre lasers can also be used to weld cladding tubes or endoscope guide tubes. The Fraunhofer Institute for Laser Technology (Aachen, Germany; www.ilt.fraunhofer.de) presented its latest findings at the IVAM Product Market: Micro, Nano & Materials at Hannover Fair.
“The advantage of a fibre laser over the Nd:YAG laser is its exceptional beam quality with high output rating,” says doctoral candidate Jens Gedicke, microtechnology, Fraunhofer Institute for Laser Technology. “The beam can easily be focused, and because of the small focus diameter, we can achieve a much higher intensity on the workpiece and smaller weld seams while using less power [than is possible with Nd:YAG technology]. And since less energy is reaching the workpiece, distortion is not a problem because the piece will not heat up as fast.”
Gedicke adds that another advantage of the fibre laser is its compact size, which makes it easier to integrate into a machine. “Nd:YAG lasers are much larger and need high-power current, while the fibre laser only needs a regular 220-V power outlet,” he explains.
The Fraunhofer Institute for Laser Technology is a non-profit public-benefit organization that develops methods and systems for laser materials processing and laser measuring technology within the framework of R&D contracts.
Firm Sets New Standard in Femtosecond Lasers
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The JenLas D2.fs laser is suitable for LASIK surgery as well as cold ablation micromachining. |
“Since the original launch of the JenLas D2.fs at the LASER 07 event in Munich , we have made some technological improvements to the machine,” says marketing director Ingetraud-Ute Graupner. “We have increased the repetition rate from 200 to 300 kHz. The central wavelength was adjusted to 1025 nm, the performance at 100 kHz was improved to up to 15 µJ, and the performance potential at 50 kHz was enhanced to up to 150 µm. We have also optimized the mechanics.”
Thanks to its low thermal load, the JenLas D2.fs can be used in LASIK-based refractive corrections. The machine is also suited for cold ablation micromachining applications, because enamel margins and micro-cracks are unlikely to occur. Consequently, the laser can be used to treat dental ceramics or to structure thin layers of material.
The high-energy, ultra-short-pulse laser is OEM-designed for exact integration, and uses regenerative femtosecond amplifier, diode pumping, and thin disc laser technology. Water- and air-cooled versions are also available.
