Overview
IEC 62715-6-22:2023 - Flexible display devices: Crease and waviness measurement methods specifies standard measurement conditions and procedures to quantify surface crease and waviness in one‑axis foldable display panels and modules (e.g., in‑folding and out‑folding devices). The standard defines how to prepare specimens, select measurement locations (crease zone vs. waviness zone), control atmospheric conditions, perform measurements using three main methods, and report geometrical distortion metrics for foldable displays.
Key topics and technical requirements
- Scope and applicability: Measurement of geometrical surface distortions in foldable display panels and modules with a single folding axis.
- Standard conditions: Requirements for standard atmospheric conditions and specimen preparation prior to measurement (visual inspection, mounting on base plates, orientation).
- Measurement locations: Defined areas for crease (local linear distortions along the fold) and waviness (long‑wavelength surface deviations from the basic form).
- Measurement methods:
- Non‑contact topography (surface normal / optical mapping) - captures surface normal vectors for detailed topographic analysis.
- Non‑contact profilometry (laser/optical scanning) - generates height profiles across the folding region for waviness analysis.
- Contact profilometry (stylus probe) - mechanical profiling for direct surface height measurement where applicable.
- Data analysis and reporting: Procedures for grouping and filtering profile data, deriving crease and waviness parameters, and formatting measurement reports to ensure comparability. The standard references standardized filtration and profile analysis approaches (e.g., profile filtering concepts).
Practical applications and users
- Manufacturers of foldable smartphones, tablets, laptops, and wearables - for product design validation and quality assurance of cover layers and display modules.
- Test laboratories and R&D teams - to reproducibly quantify fold‑related surface distortions during development, material selection, and reliability testing.
- Suppliers of flexible covers and films - to evaluate material performance versus crease/waviness requirements.
- Certification bodies and quality auditors - to use standardized metrics when assessing conformity, visual quality, and mechanical performance of foldable displays.
Benefits
- Enables consistent, repeatable evaluation of fold‑related surface defects.
- Facilitates comparison across materials, designs, and suppliers using standardized methods.
- Supports product improvement by linking measurable surface distortion metrics to perceived visual artifacts.
Related standards
Keywords: IEC 62715-6-22:2023, foldable displays, crease measurement, waviness measurement, flexible display testing, non-contact profilometry, contact profilometry, surface topography.
