As smartphone users demand higher screen-to-body ratios, display technologies have evolved—from large bezels to notches, pop-up cameras, and now punch-hole displays. Today, the punch-hole screen is one of the most popular and elegant solutions, offering maximum screen area while keeping the front camera functional.
But making a punch-hole screen is not easy.
🕳️ Punch-Hole Display Challenges
There are two common types of punch-holes:
Blind holes: Smaller and more integrated, but the LCD layer above the camera blocks light, reducing image quality.
Through holes: Allow full light to reach the camera, but the opening is larger and harder to integrate beautifully.
So, how can manufacturers use through-hole designs without compromising aesthetics or image quality?
The key is precise adhesive (glue) application to perfectly align the camera and display layers. That’s where chromatic confocal sensors (CFS) come in.
🔍 Why Use Chromatic Confocal Sensors (CFS)?
Our CFS sensors help detect glue height and thickness with high precision. This ensures:
Accurate alignment between camera and hole
Better image quality
Smaller hole sizes without sacrificing design
Here’s how they solve the problem:
1. ✅ Transparent Material Measurement
The glue used is transparent and curved.
Traditional sensors struggle with transparent surfaces or show errors due to light refraction.
CFS can accurately measure transparent glue thanks to its vertical light beam design.
2. ✅ Handles Curved Surfaces and Angles
Glue often forms a dome shape after dispensing.
Measuring sloped surfaces is tricky—many sensors fail if the light reflection angle is too steep.
HyberSense CFS supports up to ±62° measurement angles, capturing data even from narrow light reflections.
3. ✅ Micron-Level Accuracy
As hole diameters shrink (some as small as 4.38mm!), internal glue areas become tighter.
Our HPS-CF007 probe features a spot size as small as 10μm, perfect for these tiny spaces.
This ensures reliable glue inspection even in the smallest designs.
4. ✅ Fast Measurement for Mass Production
Speed matters in production.
Our HPS-CF series offers up to 72,000 measurements per second (72kHz)—one of the fastest in the industry.
This enables real-time, inline inspection for high-volume manufacturing lines.
🧠 Final Thoughts
Using chromatic confocal sensors in punch-hole screen production helps ensure:
Consistent glue height and thickness
Reliable image quality
Smaller, cleaner hole designs
Higher product yield and fewer defects
By detecting and solving issues at the source, CFS technology helps display manufacturers maintain quality, reduce waste, and improve customer satisfaction.
