Unique combined thermal and optical test, measurement and characterization of Light-Emitting Diode (LED) components and Solid State Lighting (SSL) arrays


TeraLED is designed to be used as an optical system for LEDs in a precisely controlled thermal environment. If used as an add-on option for T3Ster, it forms a complete JEDEC JESD51-51 and 51-52 compliant LED test setup.



To obtain combined optical/thermal measurements, T3Ster measures the thermal response of the LED under test. The photometric and radiometric characterization are performed by TeraLED. The measured emitted optical power then is considered by T3Ster when calculating the thermal metrics of the LED under test and light output characteristics shown by TeraLED are provided as a function of the real junction temperature.



The measurement procedures and the measurement results comply with the latest JEDEC LED thermal testing standards (JESD51-51 and JESD51-52).

Test a Wide Range of LEDs

A selection of 30- and 50cm diameter integrating spheres is offered to host temperature controlled DUT holder fixture solutions. Temperature controlled DUT holders (6cm diameter Peltier-based cold plate for the 30cm sphere and a liquid cooled version with 12cm internal diameter for the 50cm sphere) are provided.

Temperature stabilized reference LED and a detector system with different filters which include equispectral, V(λ), V'(λ), Xshort, Xlong and Z are standard parts of TeraLED. The detector with the photometric filter is matched to the CIE V(λ) function with 1.5% accuracy (f1' error).


Wide Range of Performance Data for Time-critical Environments

Real thermal resistance is automatically measured along with light output metrics as a function of real LED 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 even take a whole day.

Output Data for Thermal Simulation and Hot Lumen Calculations

Identified junction-to-case thermal resistance values from JEDEC JESD51-14 compliant T3Ster measurements and the automatically generated dynamic compact thermal model of LED packages describing the heat-flow path up to this junction-to-case thermal resistance value can be applied directly into CFD analysis software such as FloTHERM® and FloEFD™.

The LED package compact thermal model completed with the light ouput model obtained from TeraLED measurements allows the new FloEFD LED module to perform accurate thermal simulation of LED-based products including hot lumens calculations. The latest versions of the TeraLED software suite, the T3Ster Master software and FloEFD allow a seamless information flow for this purpose.


Options & Accessories

Optional LED Add-on Booster   Choice of Sphere Sizes
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 + TeraLED combination.   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 system with 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 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.



Technical Specifications

Optical Characteristics  
  • 30 cm Sphere: Radiant Power: 9 W Luminous Flux: 3300 lm
  • 50 cm Sphere: Radiant Power: 20 W Luminous Flux: 9000 lm
Further measured/derived quantities include: CIE 1931 2deg x-y Color Coordinates, Scotopic Flux, Radiant Efficiency, Luminous Efficacy, Efficacy of Radiation, Correlated Color Temperature
Electrical Characteristics - Forward Voltage  
  • TeraLED standalone: 0 .. 8 V
  • TeraLED + T3Ster: 0 .. 7 V
  • TeraLED + T3Ster + Booster: 0 .. 280 V
Electrical Characteristics - Forward Current  
  • TeraLED standalone: 0.005 .. 2 A
  • TeraLED + T3Ster: 0.0001 .. 2 A
  • TeraLED + T3Ster + Booster: 0.0001 .. 200 A

In case of using a booster device the electrical characteristics depend on the properties of the booster used.

DUT Holders: Inner Diameter, Reference Temperature Ranges, Heat-Sinking Capabilities  
  • Peltier-based DUT holder: Ø 55 mm / 10 .. 90 degC / 10 W
  • Liquid-cooled DUT holder: Ø 120 mm / 10 .. 90 degC / 50 W
Heat-sinking capability of the liquid-cooled DUT holder depends on the type of the applied coolant, the liquid circulation speed and the heat-sinking capability of the external chiller used. A large number of liquid-based thermostats are supported (including different models of JULABO). Maximal and minimal temperature also depends on the applied liquid.