With the rapid growth of foldable smartphone technology, major brands like Huawei, Samsung, OPPO, and Xiaomi are constantly pushing the limits of design and durability. In early 2024, Huawei launched its latest vertical foldable phone, Pocket 2—marking the 43rd foldable phone model globally since the concept debuted in 2018. In China alone, over 7 million units were shipped last year, with more than 100% year-on-year growth.
As demand rises, so do expectations: consumers want lightweight devices with improved durability, smoother folding mechanics, and flatter screens with minimal creasing. One of the most critical factors? The connection structure in the foldable screen’s flexible panel—a key area where even the slightest variation can affect screen flatness and long-term reliability.
Application: Inspection of Foldable Screen Connection Structures
Objective:
To accurately inspect the surface structure and critical dimensions of the flexible panel’s connection area, including:
Gaps
Step heights
Warping
Overall surface appearance
Challenge:
Due to the special coating materials used in the connection structure, conventional sensors struggle to measure key parameters reliably—especially on transparent, mirror-like, or high-reflective surfaces.
Our Solution: 3D Line Confocal Sensor – HPS-LCX3000
For this application, we used the Hypersen HPS-LCX3000 3D Line Confocal Sensor. It offers:
Non-contact measurement based on chromatic confocal technology
Z-axis repeatability of 0.4 µm
X-direction resolution of 4.9 µm
High-speed line scanning to create rich 2D and 3D surface profiles
Exceptional performance on materials like transparent films, mirror surfaces, and black rubber
Measurement Process:
The sensor scanned the target connection area in a single pass, capturing detailed 3D profiles. This allowed for precise evaluation of:
Surface flatness
Coating uniformity
Micro gaps and warping
Step differences between adjacent layers
Results
The HPS-LCX3000 successfully measured all required dimensions with high precision and speed, proving to be an ideal tool for inline quality control in foldable smartphone manufacturing.
Product Highlight: HPS-LCX Series
The HPS-LCX Series is designed for high-precision 3D optical inspection. It features:
High imaging resolution
Material adaptability (glass, metal, rubber, etc.)
Fast line scanning with CMOS imaging
Excellent performance even with low contrast or high-reflective surfaces
