1310nm/1550nm semiconductor laser power supply for the optical fiber measurement

A high stability and continuously adjustable 1310nm/1550nm semiconductor laser power supply was designed for accurate and rapid measurement of the optical fiber. The laser power supply uses precision constant current source to drive the semiconductor laser diodes by applying the current negative feedback control technology and constant temperature control circuit to drive thermoelectric coolers, and ensures the stability of the laser output power. The contrdler area network bus circuit realizes continuous power adjustment and laser source selection, and variable integration proportion-integration-differentiation algorithm eliminates the integral saturation and accelerates the system temperature stability. The laser power supply works reliably and stably under laser protection and soft-start circuit. The experimental results show that the system has stability of temperature of 0.01℃ and the long-term output power stability of 0.018dB when the laser works at room temperature 25℃. Compared with the traditional 1310nm/1550nm laser power supply, the system has high and fast stability, small size and facilitates the optical fiber online measurement.