Printed Circuit Boards (PCBs) are the foundation of all modern electronic devices. As devices become smaller, faster, and more complex, the need for precise PCB inspection is more critical than ever. One key area is the measurement of via holes, which connect different layers in a multi-layer PCB.
Traditional manual inspection can’t meet the speed or precision requirements of today’s manufacturing. That’s where Hypersen’s 3D Line Confocal Sensors come in.
🔍 Application Overview
Goal:
Accurately measure the depth and diameter of via holes on high-density PCBs.
Challenges:
Small hole diameters and tight spacing
Complex via structures (blind holes, buried vias, etc.)
Need for non-contact, high-resolution scanning
🛠 Sensor Selection
To meet these requirements, Hypersen used its:
🔹 3D Line Confocal Sensor: HPS-LCX1000
🔹 Controller: HPS-NB3200
This sensor uses a coaxial light path, which helps avoid blind spots caused by angled surfaces or shadows — ideal for inspecting small holes closely packed together.
🧪 Test Setup
The system was tested in a lab environment with the following parameters:
Scanning frequency: 4000 Hz
Point spacing: 1.1 µm
Line spacing: 4 µm
Scanning speed: 16 mm/s
The sensor scanned a PCB sample, capturing a 3D point cloud of the surface, including the via holes.
✅ Results
From the 3D data:
Both depth and diameter of blind holes were clearly measurable
Position and shape of each via hole were visible
Color maps helped visualize surface height differences
Minor variations (e.g., ink marks, machine tolerances) were also detectable
This shows that Hypersen’s sensor can not only detect via defects, but also analyze fine surface geometry with micron-level precision.
📌 Conclusion
Via hole inspection is just one of many PCB quality control challenges. Other applications include:
Solder mask inspection
Trace width measurement
BGA soldering analysis
Hypersen’s 3D Line Confocal Sensors offer non-contact, high-speed, high-precision measurements for reflective, absorbent, and transparent materials — making them a powerful tool in modern PCB manufacturing.
