IEC 61747-40-1:2019

Overview

IEC 61747-40-1:2019 - Liquid crystal display devices - Part 40-1: Mechanical testing of display cover glass for mobile devices - Guidelines provides guidance for mechanical performance testing of display cover glass used in mobile electronic devices. The standard focuses on key mechanical attributes - primarily strength and damage resistance - and addresses testing at the cover‑glass level only. This edition (2019) updates test relevance for mobile applications, withdraws unsuitable methods, adds an abraded strength method, clarifies links between test methods and fracture modes, and revises terms and definitions.

Key topics and technical requirements

• Scope and focus: Mechanical testing guidelines for cover glass in mobile device displays; applies to as‑received and strengthened glass (chemical or thermal).
• Primary attributes covered:
  • Edge strength (originating from edge flaws)
  • Surface strength (surface flaw-driven failure)
  • Impact resistance / energy‑to‑failure (surface blunt impact)
  • Surface damage resistance (scratch, indentation, sharp contact)
  • Retained (abraded) surface strength
• Representative test methods (guideline links to companion test documents):
  • Uniaxial flexural strength (four‑point bend) - edge strength
  • Biaxial flexural strength (ring‑on‑ring) - surface strength
  • Biaxial flexural energy‑to‑failure (ball drop) - impact resistance
  • Sharp contact / ball‑drop on abrasives - propagated damage under rigid support
  • Abraded biaxial flexural strength - retained strength after defined abrasion
  • Scratch and indentation tests - visual crack/retained strength assessment
• Test environment: standard laboratory conditions are specified as 23 °C ± 3 °C and 50 % ± 5 % relative humidity to control fatigue effects; deviations must be reported.
• Strengthening considerations: Guidance recognizes chemically strengthened (ion‑exchange) and thermally strengthened glass and notes their influence on measured mechanical performance.

Applications and who uses this standard

IEC 61747-40-1:2019 is practical for:

• Display and cover‑glass manufacturers validating mechanical durability for mobile devices
• Material suppliers developing chemically or thermally strengthened glass
• OEMs (smartphone, tablet, wearable) specifying mechanical acceptance criteria
• Independent test laboratories performing cover‑glass mechanical testing
• R&D and QA teams assessing fracture modes, abrasion resistance, and retained strength after damage

Use cases include product design validation, supplier qualification, failure analysis, and comparative benchmarking of cover glass technologies.

Related standards

Parts referenced in the guideline matrix include companion test documents in the IEC 61747 series such as:

• IEC 61747-40-2 (edge strength - four‑point bend)
• IEC 61747-40-3 (ball‑drop / energy‑to‑failure)
• IEC 61747-40-4 (ring‑on‑ring surface strength)
• IEC 61747-40-5 (sharp contact / propagation under rigid support)
• IEC 61747-40-6 (abraded strength testing)

For procurement, compliance, or test planning, combine IEC 61747-40-1:2019 guidance with the specific test method parts listed above.