IEC 62899-302-3:2021

Overview

IEC 62899-302-3:2021 - "Printed electronics - Part 302-3: Equipment - Inkjet - Imaging-based measurement of drop direction" specifies in-flight, imaging-based methods for measuring the direction of ink drops jetted from drop-on-demand inkjet print-heads used in printed electronics. The standard describes how to use optical drop watchers (single, double or strobe flash) to determine both 2-D projected angles and full 3-D trajectory angles of jetted drops. It explicitly excludes holographic/interference techniques and any methods that assess deposited (post-impact) drops.

Key technical topics and requirements

• Measurement scope:
  • Applies only to in-flight imaging of drops from drop-on-demand print-heads (printed electronics equipment).
  • Does not cover holographic/interference methods or deposited-drop assessments.
• Measurement methods:
  • Six defined methods: projected-angle measurement using one drop watcher (methods 1–3: double flash, single flash, strobe) and trajectory-angle measurement using two drop watchers (methods 4–6).
  • Annex A contains measurement formulae, schematics and image-recording guidance for each method.
• Instrumentation and calibration:
  • All trajectory measurement equipment must have a carefully calibrated geometry.
  • Image plane alignment: the imaging plane must be aligned precisely orthogonal to the inkjet nozzle plane before measurements.
• Reporting and reproducibility:
  • Measurement processes require reporting of conditions (see Clause A.3) and explicit statement of geometry, reference directions and delays used.
• Normative reference:
  • Refers to IEC 62899-302-1 for related imaging-based jetting-speed measurement methods.

Practical applications and who uses this standard

• Printed electronics equipment manufacturers: validate print-head performance, ensure accurate drop placement and consistent jetting direction.
• Print-head and ink developers: quantify angular spread under specific ink and waveform conditions to optimize formulation and drive signals.
• Equipment integrators and contract manufacturers: assess whether drop trajectories risk bridging adjacent conductive features (affecting yield and electrical performance).
• Metrology and quality labs: implement standardized in-flight imaging test procedures for QA, acceptance testing and comparative benchmarking.
• R&D teams designing high-resolution printed circuits, sensors or displays where precise drop placement is critical.

Related standards

• IEC 62899-302-1 - Printed electronics - Equipment - Inkjet - Imaging based measurement of jetting speed (normative reference).
• Other parts of the IEC 62899 series cover broader printed-electronics metrology topics (see IEC webstore for the series index).

Keywords: IEC 62899-302-3, printed electronics, inkjet, drop direction, drop watcher, in-flight imaging, drop-on-demand, projected angle, trajectory angles, measurement standard.