Overview
EN ISO 14880-4:2024 (ISO 14880-4:2024) - published by CEN/ISO - defines standardized test methods for geometrical properties of microlenses in microlens arrays. It applies to very small lenses formed on one or more surfaces of a common substrate and to graded‑index microlenses. The document is the second edition (superseding the 2006 edition) and is part of the ISO 14880 series for optics and photonics.
Key Topics
- Scope and terms: Uses terminology and symbols referenced from ISO 14880‑1; defines parameters such as pitch (Px, Py), surface modulation depth (h / lens sag), physical thickness (Tc) and radius of curvature (Rc).
- Coordinate system and definitions: Establishes a coordinate basis and measurement conventions to ensure repeatable geometrical characterization.
- Measurement methods:
- Stylus instrument and confocal microscope methods for measuring pitch and surface modulation depth.
- Micrometer methods for measuring physical thickness.
- Procedures for measuring radius of curvature, including test arrangements and equipment.
- Procedure and reporting: Detailed measurement procedure steps, interpretation of results, treatment of uncertainties and required test report content.
- Informative annexes: Includes guidance on Fizeau interferometer measurements (Annex A) and uniformity of array spacing (Annex B).
- Normative references: Cross-references to related standards (e.g., ISO 14880‑1 for vocabulary; ISO 21920‑2 for profile/roughness parameter relationships).
Applications and Who Uses It
This standard is practical for organizations that design, manufacture, test or specify microlens arrays:
- Optical and photonics manufacturers producing microlens arrays for cameras, sensors and displays.
- Quality control and metrology laboratories performing acceptance and production testing.
- Product designers and systems engineers integrating microlens arrays into modules (e.g., coupling optics for arrayed light sources and photodetectors).
- R&D groups and academic researchers working on microlens fabrication, graded‑index lenses or novel array geometries.
Typical application areas cited include 3D displays, arrayed light‑source coupling, enhanced LCD optics, and optical parallel processors.
Related Standards
- ISO 14880‑1 - Microlens arrays - Vocabulary (used for terms and symbols).
- ISO 14880‑2, ISO 14880‑3 - Other parts of the microlens arrays series (device/optical property tests).
- ISO 21920‑2 - Referenced for profile/roughness parameter relationships.
- EN adoption: This ISO edition is published as EN ISO 14880‑4:2024 and is to be implemented by CEN member bodies.
For manufacturers and labs, adopting EN ISO 14880‑4:2024 ensures consistent, comparable geometrical measurement of microlens arrays and supports interoperability across suppliers.
