Optics and Precision Engineering, Volume. 31, Issue 16, 2319(2023)
Method for unattended measurement of surface reflectance in field sites
Figures & Tables(24)
Fig. 2. Pictures of automatic surface reflectance monitor installation
Fig. 3. Composition of automatic diffuse-to-global irradiance ratios monitor
Fig. 4. Pictures of automatic diffuse-to-global irradiance ratios monitor installation
Fig. 6. Annual variation curve of noon solar elevation angle in Dunhuang
Fig. 7. Lambert correction coefficients at different solar elevation angles
Fig. 8. Measured reflectance of the field by whiteboard method （Day 1，
Table 1. Specifications of the automatic surface reflectance monitor
View tableView in ArticleTable 1. Specifications of the automatic surface reflectance monitor
Spectral range 350~2 500 nm Spectral resolution 4 nm@350~1 000 nm
10 nm@1 000~1 900 nm
7 nm@1 900~2 500 nm
Field of view 4° Accuracy of reflectance measurement 0.01 （Non-absorbing band） Operating environment temperature -20~60 ℃
Table 2. Specifications of automatic diffuse-to-global irradiance ratios monitor
View tableView in ArticleTable 2. Specifications of automatic diffuse-to-global irradiance ratios monitor
Spectral range 350~2 500 nm Spectral resolution 4 nm@350~1 000 nm
10 nm@1 000~1 900 nm
7 nm@1 900~2 500 nm
Field of view 180° Accuracy of diffuse-to-global ratios measurement 0.01 （Non-absorbing band） Operating environment temperature -20~60 ℃
Table 3. Uncertainty of the coefficient of irradiance method
View tableView in ArticleTable 3. Uncertainty of the coefficient of irradiance method
Relative uncertainty of reflectance of whiteboard 1.029% Lambert correction of whiteboard ≤0.005 Relative uncertainty of radiance measurement ≤0.5% Relative uncertainty of irradiance measurement ≤0.5% Composite relative uncertainty ≤1.345%
Table 4. Uncertainty of reflectance measurement
View tableView in ArticleTable 4. Uncertainty of reflectance measurement
Standard whiteboard method Irradiance method Relative uncertainty of reflectance of whiteboard 1.029% Relative uncertainty of reflectance calibration coefficient ≤1.345% Lambert correction of whiteboard ≤0.005 Relative uncertainty of surface radiance measurement ≤0.5% Relative uncertainty of whiteboard radiance measurement ≤0.5% Relative uncertainty of irradiance measurement ≤0.5% Relative uncertainty of surface radiance measurement ≤0.5% Composite relative uncertainty ≤1.520% Composite relative uncertainty ≤1.345% Composite absolute uncertainty ≤0.005 3 Composite absolute uncertainty ≤0.004 7
Tools
Get Citation
Copy Citation Text
Zhiwei XIA, Shuo WANG, Xiaolong YI, Yupeng WANG, Wei FANG. Method for unattended measurement of surface reflectance in field sites[J]. Optics and Precision Engineering, 2023, 31(16): 2319
Paper Information
Category: Modern Applied Optics
Received: Jul. 13, 2022
Accepted: --
Published Online: Sep. 5, 2023
The Author Email: WANG Yupeng (wangyp@ciomp.ac.cn)
© Copyright 2018-2021 | Chinese Laser Press.
All Rights Reserved 沪ICP备15018463号-20