Innovative LED illumination technology

Breaking the limits of optical inspection with special system set-up of Gel-Light LED illumination

Highly-precise 100% inspection solution for BOPP, PET
and BOPET films due to highly sophisticated light technology

Innovative LED illumination technology
adds a new dimension to the quality
inspection of transparent films

Mobile communication devices such as smartphones and tablet PCs, as well as flat-screen TVs are in demand as never before, resulting in more challenging customer requirements. Manufacturers of optical film for TFT displays have noticed a significant increase in quality demands, too. Defective film results in display errors and eventually in nonmarketable products. In order to avoid expensive customer complaints, inspection systems provide an ideal solution. The technologies applied by ISRA allow for identifying and classifying even the smallest of defects which are not visible to the human eye - a clear competitive advantage.

Each step in the production of flat-screens entails high added value. Purchased parts must therefore meet the highest quality standards. Defective products must be recognized and sorted out as early as possible. This also applies for optical films. ISRA's new GEL-Light with LED technology is revolutionary for their inspection systems regarding the quality control of transparent films such as BOPP, PET and BOPET. The innovative, patented illumination technology allows for detecting defects down to a size of under 50 µm as soon as in the extrusion line of film production. Such defects have not been detectable by previous systems and could nevertheless result in optical defects in TFT screens.

ISRA offers inspection solutions in three categories according to the relevant requirements: Standard, Advanced and Premium. The Standard system is capable of detecting defects down to a size of 100 µm, the Advanced version identifies irregularities down to 50 µm or even smaller ones upon request. This allows for detecting fish eyes, gels, black specs, scratches, holes and needles, the latter being exclusive to the Advanced version. In addition, the GEL-Light tilted concept used in the Premium category also identifies fine scratches and contamination below the resolution limit. The classification of scratches and point defects has been significantly improved; defects may be displayed according to type and size. Consequently, the customer is provided with additional information on the type of identified defects - an important aid for production optimization.

Film manufacturers also benefit from the proven Multi-View and Multi-Mode technologies. While several camera beams were required for securely detecting defects in the past, a single camera beam now manages this task. The ultra-rapidly switchable LED illumination units for incident and transmitted light allow for measuring in reflection and transmission, resulting in the detection of even small defects. This innovative technology also impresses due to its extreme brightness as well as the possibility to flash the LED precisely at highest web speeds and synchronize them with the camera used, even at high frequencies. The reduction in mechanical features and components results in further increased reliability and minimal maintenance.

Conclusion: By combining GEL-Light with LED technology, Multi-Mode and Multi-View, up-to-date processor technology, solid camera technology as well as highly efficient software algorithms, ISRA inspection systems reliably detect even the smallest of defects at high web speeds. The high defect detection rate and improved defect classification furthermore form the basis for substantiated analysis and the optimization of production processes. Altogether, ISRA inspection systems support continuously high product quality, minimum scrap rates and the reduction of expensive customer complaints.