半导体激光器是光纤传感系统中的重要组成部分之一, 它的输出功率和波长的稳定性决定着整个光纤传感系统的测量精 度, 为了满足传感系统的测量需求, 需对其波长进行调谐, 并且在调到所需波长后还需其具有较高的稳定性。通过温度控制 和驱动电流控制对半导体激光器波长调谐进行了研究。以往的调谐多为盲目调节, 由于驱动电流的变化会导致温度变化, 二 者之间会相互影响, 调谐过程复杂、时间长、不易调到最佳状态。提出了一个描述以波长 λ 与功率P作为输出量, 以驱动电 流I与温度T作为输入量的2×2关系矩阵, 并测定了矩阵中4个元素的值。利用这个关系矩阵, 可按照不同波长与功率的需求, 直接计算出调谐驱动电流与温度的最佳值, 使得调谐过程变得更加高效准确。设计了高稳定性TECAL-XV-XV-DAH温度控制器, 以及激光器驱动电路和温度控制电路, 实现了调谐范围3.2 nm、精度0.01 nm、漂移小于0.002 nm, 功率波动小于3 μW的激 光器调谐。

Semiconductor laser is one of the most important components in optical fiber sensing system. The stability of its output power and wavelength determines the measurement accuracy of the whole optical fiber sensing system. In order to meet the measurement requirements of the sensing system, it is necessary to tune its wavelength, and after tuning to the required wavelength, it needs to have a higher stability. In this paper, the wavelength tuning of semiconductor lasers is studied by temperature control and driving current control. In the past, the tuning is mostly blind. Because the change of driving current will lead to the change of temperature, the two will affect each other. The tuning process is complex, time-consuming and difficult to tune to the best state. In this paper, a 2×2 matrix describing the relationship between wavelength λ and power P as output and driving current I and temperature T as input is presented. The values of four elements in the matrix are determined. Using this matrix, the optimum tuning driving current and temperature can be calculated directly according to the requirements of different wavelength and power, which makes the tuning process more efficient and accurate. High stability TECAL-XV-XV-DAH temperature controller, laser driving circuit and temperature control circuit are designed. Laser tuning with tuning range of 3.2 nm, precision of 0.01 nm, drift of less than 0.002 nm and power fluctuation less than 3 μW is realized.