激光大动态范围线性测量

为研究探测器在单色光照射下大动态范围的辐射响应度是否不变，建立了基于激光的线性测量装置，并对该装置的测量不确定度进行评价。实验根据双光路叠加法，分别采用功率和照度两种模式研究了光电探测器的线性。对于功率模式，实验测量了6个数量级光功率变化下探测器的大动态范围非线性系数；对于照度模式，将激光导入积分球输出光辐射，测量了探测器在3个量级变化下的非线性系数。实验结果表明:当激光功率模式下探测器的输出电流从0.2 mA变至0.2 nA，探测器的非线性系数全部小于±0.02%；当激光照度模式下探测器光电流从200 nA变为0.2 nA，探测器非线性系数小于±0.02%。由此可知，激光线性装置可以实现功率和照度两种模式测量，满足至少6个量级以上的测量。

Measurement of absolute linearity using laser covering large-scale dynamic range

In order to investigate whether the radiometric responsivity of the detector in large-scale dynamic range is constant under the illumination of monochromatic light, a laser-based linear measuring device was established, and the measurement uncertainty of the device was evaluated. According to the dual optical path superposition method, the linearity of the photodetector was measured in both the power mode and the irradiance mode. For the power mode, the nonlinear coefficient was measured with the laser power varying over 6 orders of magnitude, while for the irradiance mode, the laser was guided into an integrating sphere to output the optical radiation, and the nonlinear coefficient of the detector under 3 orders of magnitude changes was measured. Results show that when the current of the photodetector is varied from 0.2 nA to 0.2 mA in power mode, the nonlinear fact of the detector is less than ±0.02%. When the current of the detector is changing from 200 nA to 0.2 nA in irradiance mode, the nonlinear factor is also less than ±0.02%. It can be seen that the laser linear device can realize two modes of power and illuminance measurement, and meets the measurement of at least 6 orders of magnitude or more.