Forward voltage short-pulse technique for measuring high power laser array junction temperature

• Published in: NASA Center for AeroSpace Information (CASI). Misc. Resources
• Main Authors: Meadows, Byron L, Amzajerdian, Frazin, Barnes, Bruce W, Baker, Nathaniel R
• Format: Web Resource
• Language: English
• Published: Hampton NASA/Langley Research Center 07.02.2012
• Subjects: Continuous radiation; Current pulses; Diodes; Electric potential; Laser arrays; Lasers; Light emitting diodes; Low currents; P-n junctions; Semiconductor lasers

The present invention relates to a method of measuring the temperature of the P-N junction within the light-emitting region of a quasi-continuous-wave or pulsed semiconductor laser diode device. A series of relatively short and low current monitor pulses are applied to the laser diode in the period between the main drive current pulses necessary to cause the semiconductor to lase. At the sufficiently low current level of the monitor pulses, the laser diode device does not lase and behaves similar to an electronic diode. The voltage across the laser diode resulting from each of these low current monitor pulses is measured with a high degree of precision. The junction temperature is then determined from the measured junction voltage using their known linear relationship.