Calibration of an illuminance meter is indispensable for accurate measurement of the illuminance of indoor lighting and daylight. In recent years, because of the phasing-out of incandescent lamps and their replacement with LED lamps, it has become difficult to obtain an incandescent type standard lamp to calibrate an illuminance meter. To replace the standard lamp method, we constructed an illuminance meter calibration system based on an LED-based spectrally tunable light source. The approximate CIE Illuminant A spectrum realized by the LED-based spectrally tunable light source was controlled at various illuminance values (800–10,000 lx). A test illuminance meter was calibrated by comparison against a reference photometer with the realized approximate Illuminant A spectrum. The illuminance values measured using the reference photometer and using the test illuminance meter in the calibration system agreed within 2.5% without reference plane correction of the test illuminance meter, and within 1% with reference plane correction. Reference plane correction depends strongly on the measurement distance and the illuminance meter structure. This study demonstrated that it can be improved. Therefore, we infer that an illuminance meter calibration method using an LED-based spectrally tunable light source is a promising means of overcoming difficulties posed by the phasing-out of incandescent standard lamps.

中文翻译：

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使用 LED 光谱可调光源校准照度计

照度计的校准对于准确测量室内照明和日光的照度是必不可少的。近年来，由于白炽灯的淘汰和LED灯的替代，获得白炽型标准灯来校准照度计变得困难。为了取代标准灯法，我们构建了一个基于 LED 光谱可调光源的照度计校准系统。由基于 LED 的光谱可调光源实现的近似 CIE 光源 A 光谱被控制在各种照度值 (800–10,000 lx)。通过与具有实现的近似光源 A 光谱的参考光度计进行比较来校准测试照度计。使用参考光度计和校准系统中的测试照度计测得的照度值在未经测试照度计参考平面校正的情况下在 2.5% 以内，在有参考平面校正的情况下在 1% 以内。参考平面校正很大程度上取决于测量距离和照度计结构。这项研究表明它可以改进。因此，我们推断使用基于 LED 的光谱可调光源的照度计校准方法是克服逐步淘汰白炽灯标准灯所带来的困难的有希望的手段。参考平面校正很大程度上取决于测量距离和照度计结构。这项研究表明它可以改进。因此，我们推断使用基于 LED 的光谱可调光源的照度计校准方法是克服逐步淘汰白炽灯标准灯带来的困难的有前途的手段。参考平面校正很大程度上取决于测量距离和照度计结构。这项研究表明它可以改进。因此，我们推断使用基于 LED 的光谱可调光源的照度计校准方法是克服逐步淘汰白炽灯标准灯所带来的困难的有希望的手段。