The direction of measurement

The lighting direction of light emitting diode is very strong, the position of measuring direction will significantly influence the accuracy of the measured results. Especially in the measurement of LED axial light intensity, some instruments don’t make limit for the direction of the measured LED, thus it is difficult to guarantee the precision of measurement.

In the test of the power supply for the LED driver (LED driver testing), the increased temperature of LED junction that influences on electric parameters and lighting can not be ignored. Therefore, the balance of environment temperature and device temperature is an important measurement condition when test.