Reason Analysis of Poor Measurement Accuracy of Ultraviolet Illuminance Meter
(1) The uncertainty of the ultraviolet base (standard) standard is several times higher than that of the photometry.
(2) There are no strict unified regulations on the spectral response characteristics of ultraviolet measuring instruments at home and abroad. For visible light, as early as 1924, the International Commission on Illumination (CIE) announced the photopic spectral luminous efficiency V(λ), which can be corrected to be consistent with V(λ) by the combination of photodetectors and filters, so , the measurement accuracy is high.
(3) The probe of the ultraviolet radiation illuminance meter is less stable than the visible light probe under long-term ultraviolet light (especially strong ultraviolet light) irradiation and long-term storage.
(4) There are many kinds of ultraviolet radiation sources, and the composition of their spectral components is often quite different, while the calibration of the ultraviolet radiation illuminance meter is carried out under the irradiation of a specific radiation source, which lacks universality for various ultraviolet radiation sources .
(5) The geometric conditions in the application measurement are various, which are generally quite different from the geometric conditions in the calibration of the irradiance meter.
In addition, scholars have focused on giving detailed quantitative evaluation methods for nonlinear response errors, directional response errors, temperature-dependent response errors, fatigue errors, and responses to visible radiation generated during measurement.
In the concluding remarks, the scholars put forward that in addition to the reasons for the poor measurement accuracy of the ultraviolet radiation illuminance meter described above and the quantitative evaluation of the measurement error, there are also instability of absolute spectral responsivity; zeroing drift; influence of magnetic field; range change Instability of test equipment caused by power supply changes; response time; non-quantitative errors caused by observer's shading, etc., should also be avoided and eliminated as much as possible.
