Is the future of lighting in OLED?

IEC publishes Standard for new lighting technology

By Morand Fachot

The lighting market has been concentrating on energy-efficient solutions for years. After lamps relying on light emitting diode (LED) technology, new solutions based on organic LED (OLED) are emerging. Relevant International Standards for these are being developed by IEC Subcommittee (SC) 34A: Lamps. One such Standard covers performance requirements for OLED panels for general lighting.

OLED illuminated stairs OLED illuminated stairs (Photo: GE Lighting)

Don’t be misled: LED and OLED are different

LED-based lighting is now quite widespread and popular. As countries introduce mandatory energy-efficient measures that include lighting, LED lamps, which have sharply dropped in price, are rapidly replacing tungsten, halogen or fluorescent lamps. The IEA estimates that “in 2015 LEDs led to global electricity savings of 100 terawatt-hours (TWh)”

LED lamps present the advantage that they can be retrofitted in fixtures designed for older lamps, they last much longer and are much more energy efficient than older ones.

LEDs are point source light sources, whereas OLEDs are surface emission devices. For instance instead of a bulb, like in LED lights, OLED use panels containing one or more OLED tiles, which are the smallest OLED light source, as well, as a connector, a printed circuit board and passive electronic components.

OLEDS can be used in applications such as light tiles, light partitions or transparent light sources, which only emit light at night, by day or serve as a window.

According to the lighting manufacturer OSRAM, “the efficiency of serial production OLEDs is currently around 25 lm/W. This means that they are more efficient than conventional incandescent or halogen lamps, but still can not reach the efficiency of fluorescent lamps and LEDs.” 

International Standard for OLED

IEC SC 34A published IEC 62922:2016, which “specifies the performance requirements for OLED tiles and panels for general lighting for use on DC supplies up to 120 V or AC supplies up to 50V at 50 Hz or 60 Hz for indoor and similar general lighting purpose.”

This Standard follows two other OLED lighting-related publications, IEC 62868:2014, Organic light emitting diode (OLED) panels for general lighting – Safety requirements, and IEC TS 62972:2016General lighting – Organic light emitting diode (OLED) products and related equipment – Terms and definitions.

This Standard specifies general test conditions as well as general and specific tests for stabilization (current-driven and voltage-driven), marking, information on reliability of electrical connection, and input power.

Photometric characteristics are important for lighting solutions. IEC 62922 specifies general and specific values for photometric characteristics including: luminous flux, luminous efficacy, chromaticity coordinates, correlated colour temperature (CCT), colour rendering index (CRI), luminance uniformity and intensity distribution.

The Standard also sets various conditions for reliability for high-humidity operation and high-humidity storage in high temperature conditions, and for reliability of connection.

The Standard includes a number of annexes containing additional information for measuring methods, controlgear design and information for luminaire design.

With this publication, IEC TC 34 and its SCs are set to play a central role in developing International Standards for a technology that will undoubtedly find applications in many settings, like office and commercial spaces, if not yet into every homes.

Assessing the potential for the OLED lighting market, analysts from IDTechEx forecast that it will reach USD 2,2 billion in 2026. IEC standardization work will underpin this growth.

Gallery
Scriptus office OLED luminaire Scriptus office OLED luminaire (Photo: Osram)
Philips ThinAir OLED panel ThinAir OLED panel (Photo: Philips)
OLED illuminated stairs OLED illuminated stairs (Photo: GE Lighting)