OLED system-level functional and reliability testing services
For the environmental testing of OLEDs several climate chambers are available: temperature range -70 °C – 150 °C, relative humidity can be set to 10-90 % for 10 °C < T < 90 °C.
Environmental testing services expertise:
- High-Low temperature
- Temperature and Humidity (85/85)
- Thermal shock
- Thermal cycling
- Water Vapor Transmission Test (WVTR)
Example: Happonen et.al, IEEE Transactions on Device and Materials Reliability, 14(4), 1005-1012 (2014)
Specific mechanical tests for flexible (OLED) devices and components:
Failure strain of brittle layers on flexible substrates
Two methods are available for determining failure strain: a 2-Point Bending (2PB) and a 2-Point Rotation (2PR, shown in photograph).
Using these methods the electrical resistance of a (conductive) brittle layer is determined when a controlled bending radius is applied. A resistance increase is observed upon failure. It is also possible to test a non-conductive layer after application of a thin conductive layer.
Example: Guan et.al, J. Appl. Phys. 113, 213512 (2013)
Cyclic bending tests for flexible devices
Manual and automated cyclic bending tests can be performed on flex-to-flex interconnections, components and devices. A large range of roll diameters (7-100 mm) are available for manual testing. With the automated cyclic bending tests, available for thinner devices, a large number of cycles (>> 1000) can be run, and it is also possible to have the devices operational during testing.
Example: Happonen, T. Reliability studies on printed conductors on flexible substrates under cyclic bending (Doctoral dissertation). Acta Universitatis Ouluensis. C, Technica C571 (2016)
The Sebastian MPE force tester is a force testing system optimized for production, quality control and engineering applications. The force tester system consists of a powerful, yet easy-to-use console to characterize the pull-off strengths of variable material combinations.
Comprehensive characterization of OLEDs can be performed providing electro-optical (luminance, quantum efficiency, luminous efficacy, colour temperature, colour point) characteristics, luminous intensity distribution and determination of the luminance degradation under long-term operation.
Goniometric evaluation of OLEDs
The functional testing service provides measurements of both luminous flux and light distribution of luminaires. The Near Field Goniometer system is designed for measuring light distribution of large luminaires.
The system consists of a CCD camera with spectrometer, which measures luminous flux (lm) and luminance (cd/m2).
Functional testing platform for OLED s
The functional testing platform is capable of handling both sheets and rolls. The automatic winding/rewinding testing platform consists of interconnection mechanics, interchangeable layout-specific fixtures and cross-connections.
The functional tester capabilities include on-line power feeding for OLEDs, measuring the fundamental electrical parameters and assessing the illuminated light intensity.
More information: http://pi-scale.eu/contacts/