Measuring the Impossible With 3D Line Confocal Sensors
Published on : Sunday 30-08-2020
Line Confocal Imaging (LCI) is a unique optical technology for metrology requiring resolutions down to 50 nm. In the past, confocal technology was limited to a single point or multipoint sensors based on a coaxial design. LCI developed a novel off-axis confocal technique that offers a line scan capability with benefits over the traditional coaxial approach.
3D Line Confocal Sensors Application Instances
• Curved Edge Display Inspection
Excellent Performance on Large Surface Angles
Line confocal sensors are used to scan, measure, and inspect the profile of curved screen glass used in cell phone and tablet designs at a surface angle of up to +/- 20 degrees making this sensor ideal for quality control of 2.5D and 3D display glass. Conventional vision solutions can only capture quality data on surface angles of +/- 7 degrees or less.
• Multilayered Transparent Material Inspection
Line confocal sensors are ideal for transparent material inspection and quality control. One of the critical applications in capturing the surface of mobile device displays and detecting layers inside and under the screen.3D Line Confocal Sensors
The combination of 3D tomography (multi-layer) and 2D intensity imaging is used to identify defects such as delamination, scratches, or dust on the surface or inside of laminated glass, mobile phone displays, or any other type of transparent multilayered material like sealed medical packages. And, contrary to different kinds of imaging systems, line confocal sensors detect not only the location of the defect, but they also identify in which layer the flaw exists. The sensor even measures the dimensions of the fault down to the sub-micron level.
Medical Applications
3D line confocal sensors can scan the depth and shape of embossed and etched 3D features, parting line flash of molded parts, surface roughness and texture of extruded parts and web products, and burr height in precision-stamped and micro-machined medical details.
One of the most common applications leveraging the extensive measurement range of tomographic line confocal imaging is the non-destructive inspection of completeness and integrity of heat seals in sterile medical packages.
Conclusion
3D line confocal sensors provide a highly specialized vision solution for the most challenging, complex measurement applications. Their ability to simultaneously generate 3D tomography, 3D topography, and 2D intensity data allows these sensors to perform high accuracy measurement tasks that conventional solutions cannot solve, such as scanning and quality inspection of curved, transparent, multilayered, and highly reflective materials. Besides, these sensors offer much faster scan rates than competing metrology-grade technologies, making them suitable for inline production environments.