A novel experimental method for temperature measurement of high power diode laser

Temperature is a significant parameter for evaluating the cooling efficiency of the electronic equipment. But it is difficult to measure with high accuracy when it comes to the high power diode lasers due to their small size and large temperature gradient. To handle this micro scale measurement issue, a novel experimental method was proposed based on similarity principle to enlarge the size of laser chips. Through analysis, ξ, Re and Pr are the most important dimensionless numbers which should be equal to each other if the laser chips and their heat sinks are enlarged without changing of the temperature field. By measuring the temperature of the enlarged simulated heat source, the chip's temperature can be obtained with high accuracy. Numerical simulations were done to validate the correctness of this method. The results show well correspondence in the small model and its 3 times larger model. The measurement uncertainty analysis shows that it can be an effective method for improving the temperature measuring accuracy of the laser chip.