Overview
ISO/TR 14880-5:2010 - Optics and photonics: Microlens arrays - Part 5: Guidance on testing is a Technical Report that provides practical guidance for selecting and applying test methods to microlenses and microlens arrays. It covers very small lenses formed on or within a common substrate and focuses on measurement of both optical and geometrical properties for single microlenses and full arrays. The document helps users choose appropriate ISO test standards and measurement equipment based on the parameter to be measured, lens size/structure, and intended application.
Key technical topics and requirements
- Scope and terminology: Uses definitions from ISO 14880‑1 and aligns symbols/units to a standard coordinate system for consistent reporting.
- Test conditions and handling: Recommends proper environmental and handling conditions (clean optics, controlled conditions) as referenced in relevant parts of ISO 14880.
- Measurement guidance: A decision-oriented test guide (including a flow chart) for choosing measurement methods depending on the required parameter.
- Parameters addressed (examples from the report):
- Optical: effective front/back focal lengths, numerical aperture (geometrical and diffraction‑limited), wavefront aberration (rms), focal spot size/position, imaging quality (MTF), coupling efficiency, effective Abbe number (chromatic behavior).
- Geometrical: lens radius and width, pitch, lens density, radius of curvature, substrate thickness, aperture center coordinates, surface modulation depth, array uniformity.
- Recommended equipment and methods: Links parameters to equipment such as interferometers (including Shack‑Hartmann), confocal measurement systems, microscopes with linear scales, stylus instruments, refractometers (Abbe/Pulfrich), image sensor cameras, gonio photometers, and collimated source + microscope setups.
- Reporting: Clause on test report content to ensure reproducible, comparable results.
- Informative annexes: Measurement guide (Annex A) and discussion of related ISO 14880 annexes (Annex B).
Practical applications and who uses it
- Applications: Design verification and production testing for microlens arrays used in 3D displays, LED/photodetector coupling, enhanced LCD optics, optical parallel processors, and other micro‑optical systems.
- Users:
- Optical engineers and metrology specialists selecting test methods for micro‑optics.
- QA and production teams implementing inspection procedures for microlens fabrication.
- R&D groups comparing supplier components or developing new microlens array technologies.
How to use this guidance (practical steps)
- Identify the parameter(s) to measure (e.g., focal length, wavefront error, pitch).
- Consult ISO/TR 14880‑5 equipment guide and select the recommended standard test method (e.g., ISO 14880‑2 for wavefront).
- Prepare samples under the recommended test conditions and clean optical surfaces.
- Execute measurements with appropriate metrology tools and document results per the test report clause.
Related standards
Keywords: ISO/TR 14880-5:2010, microlens arrays testing, microlens measurement methods, optical metrology, wavefront aberration, numerical aperture, confocal measurement, interferometer.