Surface Defect Detection

Roll-2-Roll® sensors work on nearly all web materials, including many that defeat conventional sensors:

• Clear films — PET, BOPP, cellophane, and other transparent materials work without special settings
• Mesh and porous webs — accurately measured where conventional sensors fail
• Metals and foils — aluminum, copper, steel strip
• Textiles and nonwovens
• Glass and carbon fiber

The patented light-scattering and spatial-filtering technology detects edges and features regardless of material opacity or surface finish. No recalibration is needed when switching between materials.

One capability is unique to Roll-2-Roll® sensors: detecting clear film edges under vacuum. Ultrasonic sensors cannot function without air as a transmission medium, and camera-based systems struggle with transparent materials. Roll-2-Roll® sensors are the only sensing technology that reliably detects clear films in vacuum environments.

The one challenging material is matte carbon black — the solution is to angle the light source perpendicular to the web to increase light scattering at the edge.

Yes. Because each Roll-2-Roll® sensor is a linear imaging array — not a point sensor — it sees the full profile of the web at capture rates up to 1,000 Hz.

Tape splices, operator flags, tears, and voids all change that profile in detectable ways. The sensor and controller identify these changes in real time:

• Splice detection — tape splices and overlaps create a measurable change in the web profile that triggers an alert or output signal
• Flag detection — operator-placed flags and registration marks are detected across a wide sensing window (up to 48 mm for mark detection vs. 2–8 mm for conventional sensors), significantly reducing setup sensitivity
• Tear and void detection — holes, tears, and missing material show up as gaps or profile changes across the pixel array
• Thread and string counting — individual threads are resolved and counted using the sensor resolution (as fine as 0.0635 mm)

The same sensor-controller combination handles these inspection tasks alongside edge guiding or width measurement — no second system, no additional hardware required.

When you need vision-like inspection capabilities but a camera-based machine vision system would be overkill for the application.

Machine vision systems excel at complex pattern recognition and two-dimensional image analysis, but they require programming, calibration, controlled lighting, and a vision expert to deploy and maintain. Roll-2-Roll® sensors fill the gap for applications where spatial awareness matters but full 2D imaging is unnecessary:

• Splice detection — identify tape splices, overlaps, and joints in real time
• Flag detection — detect operator flags and registration marks with a 48 mm sensing window (vs. 2–8 mm for conventional mark sensors)
• Tear and void inspection — detect holes, tears, and surface anomalies across the web
• Multi-strip width monitoring — measure multiple strip widths and gaps simultaneously
• Thread counting — count individual threads or strings

Roll-2-Roll® sensors deliver these inspection capabilities with zero programming, zero calibration, and setup in minutes — making them the practical choice when traditional sensors are not enough but a full vision system is more than you need.

No. A Roll-2-Roll® sensor is actually a line scan camera with vision-like capabilities, packaged with the simplicity of a sensor.

Traditional edge sensors give you a single-point measurement — one edge position, one signal. Roll-2-Roll® sensors have 768 to over 14,000 pixels, integrated LED lighting (infrared, ultraviolet, or white light options), and adaptive algorithms that provide spatial awareness across the full sensing range.

This means a single Roll-2-Roll® sensor can handle:

• Edge detection — up to 128 edges simultaneously
• Width measurement — real-time, across ranges up to 960 mm
• Splice detection — tape splices, overlaps, and joints
• Flag detection — operator flags, markers, and registration marks
• Thread counting — individual thread or string detection
• Tear and void inspection — holes, tears, and surface anomalies

All of this without machine vision complexity. The same sensor-controller combination can be repurposed across entirely different applications without hardware replacement — significantly reducing ownership costs.

Both Roll-2-Roll® sensors and traditional line scan cameras capture one-dimensional scans to build profiles of continuously moving webs. However, Roll-2-Roll® sensors use patented linear fiber-optic arrays instead of circular lenses. This fundamental difference delivers several advantages:

• 100x more light sensitivity — larger pixels (63.5 µm vs. 5–14 µm in conventional cameras) capture significantly more light per pixel
• Working distance under 15 mm — the 1:1 magnification of fiber optics enables compact installations in tight spaces
• Zero lens distortion — linear fiber optics behave like telecentric lenses, eliminating the aberrations and geometric errors inherent in circular optics
• No vision engineer required — adaptive edge detection algorithms are built in, so setup takes minutes instead of the weeks typically required for traditional line scan camera integration

The result is line-scan-camera-grade measurement capability — pixel counts from 768 to over 14,000, scan rates above 200 kHz — without calibration, custom software, or specialized imaging expertise.