Power LED Combined Thermal and Radiometric/Photometric Characterization
T3Ster TeraLED offers combined thermal and radiometric/photometric characterization of high-power LEDs, used in combination with T3Ster thermal transient tester to form a comprehensive, automated LED testing station.
Thermal Characterization of Solid State Lighting
Technology Overview: LEDs offer improved efficiency compared with conventional lighting, but operate at much lower temperatures and need to be cooled by conduction rather than radiation. This webinar describes the thermal characterisation...
T3Ster TeraLED is aimed at the combined thermal and radiometric/photometric characterization of high power LEDs. The T3Ster TeraLED system is designed to be used as a special measurement environment, as an add-on option for T3Ster, or as a stand-alone optical measurement system for LEDs.
A selection of 30 cm and 50 cm diameter integrating spheres is offered to host one of our temperature controlled DUT holder fixture solutions, a temperature stabilized reference LED and detector head with a bank of different filters which include equispectral, V(λ), V'(λ), Xshort, Xlong and Z. The detector with photometric filter is matched to the CIE V(λ) function with 1.5% accuracy (f1 error). The selection of our temperature controlled DUT holders ranges from a 6cm diameter Peltier-based cold plate with 10W heat-sinking capability up to a liquid cooled version with 12cm internal diameter and 50W of heat-sinking capability.
To obtain combined optical/thermal measurements, T3Ster is used to provide powering for the LED under test. The control of the thermal measurements and the evaluation of the thermal transients is performed by T3Ster while the measurement sequences required for the photometric and radiometric characterization are performed by T3Ster TeraLED. The measured emitted optical power then is considered by T3Ster when calculating the thermal metrics of the LED under test and the light output characteristics shown by T3Ster TeraLED are provided as function of the real junction temperature. Measurement over a wide range of forward current and LED temperature values is 100% automated thus allowing measurement in a few hours as opposed to manual procedures which could take multiple days. The measurement procedures and the measurement results comply with the latest JEDEC LED thermal testing standards (like JESD51-51 and JESD51-52).
Features and Benefits
- Developed with the needs of the LED industry in mind
- Ability to obtain combined optical/thermal measurements, consistent thermal and light output metrics
- Structure functions scaled in real thermal resistance allow exploration of LED package details
- Compliant to the latest LED thermal testing standards JESD51-51 and JESD51-52 as well as to older specs such as CIE 127-2007 standard and the JEDEC JESD 51-1 static test method
- A complete and unique solution for LED testing
- Real thermal resistance is measured along with light output metrics as function of real LED junction temperature automatically
- Test the quality of the different thermal interfaces present in SSL applications such as LED die attach, glue/solder between the package and MCPCB, the TIM applied at MCPCB – all strongly influencing LEDs’ life time and lumen maintenance
- All measurement results are compliant to the relevant industrial standards automatically, therefore measured light output metrics and/or thermal metrics are directly applicable on LED LED product datasheets
- Measurement of temperature sensitivity of luminous flux and other parameters for the purpose of hot lumens calculations in CFD-based thermal simulations
The T3Ster TeraLED software suite (offered for the control and result presentation of the T3Ster® TeraLED® system) automates procedures like measurement of emitted flux (photometric or radiant), efficiency, efficacy or chromaticity coordinates as function of temperature and/or operating current. Results are shown in form of diagrams as function of forward current and temperature. Chromaticity coordinates are shown in the CIE color diagram (CIE 1931 2 deg observer). The software smoothly operates with the T3Ster equipment and with the LED version of the T3Ster-Booster family. The LED’s electrical characteristics as well as thermal calibration diagrams are also measured. Results are presented in form of plots. The T3Ster TeraLED control electronics interfaces all devices attached to the sphere with the measurement control computer. The T3Ster TeraLED measurement control software supports automated measurements with external spectrometers attached to the TeraLED sphere through its fiber optics port. For using the liquid cooled DUT holder software support of a large variety of external third party thermostats is provided.
Options and Accessories
T3Ster TeraLED can be used in combination with the LED booster from the T3Ster-Booster family. This way multi-chip LEDs with a forward voltage beyond the 6V limit of T3Ster can also be characterized with the T3Ster+T3Ster TeraLED combination.
The T3Ster TeraLED system can be ordered either with a 30cm diameter sphere or with a 50cm diameter sphere; each sphere supplied with the appropriate temperature controlled DUT holder fixture.