阵列式光谱辐射计光学参数测量

研究了阵列式光谱辐射计校准过程中涉及的杂散光和带宽等问题。实验比较了阵列式光谱辐射计在氙灯和卤钨灯照射下进行紫外辐射测量的差异,对差异的来源-杂散光部分进行了测评。采用一组已知透过率的滤光片,通过采集有滤光片和无滤光片条件下卤钨灯的光谱,对阵列式光谱辐射计的杂散光大小进行评价,并评估了杂散光在紫外辐射测量中引起的数值偏差。实验测量了不同的阵列式光谱辐射计采集窄带光源的结果,对阵列式光谱辐射计的带宽在辐射照度计算中的影响进行评估。实验结果表明:卤钨灯照射下部分阵列式光谱辐射计在紫外300nm处的杂散光比例高达30%以上,制约了紫外辐射测量的可靠性;氙灯照射下阵列式光谱辐射计在300nm的杂散光比例可以降至5%左右;阵列式光谱仪的带宽限制了其能够准确测量光源的最小测量半高宽,几种不同带宽的阵列式光谱辐射计在365nm的测量偏差高达4%。得到的结果表明:阵列式光谱辐射计的杂散光、带宽等光学特性对测量结果的准确性影响很大。

Measurement of optical parameters for array spectroradiometers

Several kinds of optical problems involved in calibration of an array spectroradiometer were investigated, such as ultroviolet radiation, stray light, and bandwidth. The difference of ultraviolet radiation measurement of the array spectroradiometer under a xenon lamp and a tungsten halogen lamp was compared and the stray light from the measurement was evaluated. The spectra of the tungsten halogen lamp without and with optical filters were measured by using the array spectroradiometer and the deviation caused by the stray light in the ultraviolet radiation measurement was estimated. Furthermore, the narrow spectral widths captured by different spectroradiometers were measured and the effects of the bandwidths of the spectroradiometers on irradiation calculation were discussed. The experimental results for some array spectroradiometers show that the contribution of the stray light from the tungsten halogen lamp at 300 nm can be as high as 30%, and that from the xenon lamp can be around 5%. Moreover, the bandwidth of the spectroradiometers limits its ability to measure the narrow spectral width for lamps, and the measuring deviation with different bandwidths can be as high as 4% at 365 nm. These results demonstrate that the stray light and the bandwidth of array spectroradiometers are vital to its measurement accuracy.