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摘要:
为了提高可见光波段(0.3 μm~0.9 μm)高温标定的效率,提出了可见光波段高温标定的简化方法。首先,提出了带有曝光时间变量的可见光波段的高温标定模型,通过大量的实验数据发现,RGB相机各个通道的灰度值不仅随曝光时间递增呈线性变化,且随黑体辐射亮度递增呈线性变化,进而确定了可见光波段高温标定模型的具体形式。然后,为了求解简化后的可见光波段高温标定模型中的未知数,在两个黑体辐射亮度下,分别采集两个曝光时间下的图像数据,接着,对图像数据进行处理,便可以得到任意曝光时间下的RGB相机高温标定曲线。最后,对本文提出的简化可见光波段高温标定方法与常规按曝光时间进行可见光波段高温标定法进行比较。实验结果表明:R通道计算值与标定值的相对误差最大值为3.38%、G通道计算值与标定值的相对误差最大值为2.56%、B通道计算值与标定值的相对误差最大值为−1.14%,且各通道的计算值与标定值的相对误差均未超过3.50%。本文提出的数学模型可以有效地简化传统的高温标定法,进而大大的缩短了高温标定时间,提高了高温标定的标定效率。
Abstract:In order to improve the visible light band (0.3 μm~0.9 μm) A simplified method for high-temperature calibration in the visible light band has been proposed to improve the efficiency of high-temperature calibration. First of all, a high-temperature calibration model of visible light band with exposure time variable is proposed. Through a large number of experimental data, it is found that the gray value of each channel of RGB camera not only changes linearly with the increase of exposure time, but also changes linearly with the increase of Black-body radiation brightness. Then, the specific form of high-temperature calibration model of visible light band is determined. Then, in order to solve the unknowns in the simplified high-temperature calibration model of visible light band, image data under two exposure times are collected under two Black-body radiation brightness, and then the image data is processed to obtain the high-temperature calibration curve of RGB camera under any exposure time. Finally, a comparison is made between the simplified visible light band high-temperature calibration method proposed in this article and the conventional visible light band high-temperature calibration method based on exposure time. The experimental results show that the maximum relative error between the calculated value of the R channel and the calibrated value is 3.38%, the maximum relative error between the calculated value of the G channel and the calibrated value is 2.56%, and the maximum relative error between the calculated value of the B channel and the calibrated value is −1.14%. Moreover, the relative error between the calculated value of each channel and the calibrated value does not exceed 3.50%. The mathematical model proposed in this article can effectively simplify the traditional high-temperature calibration method, thereby greatly shortening the high-temperature calibration time and improving the calibration efficiency of high-temperature calibration.
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表 1在曝光时间一定的条件下RGB相机各通道的斜率(单位:DN·W−1·m2·sr)与截距值(单位:DN)
Table 1.The slope (Unit: DN·W−1·m2·sr) and intercept (Unit: DN) values of each channel of an RGB camera under certain exposure time conditions
R通道曝光时间/μs R通道斜率 R通道截距 G通道曝光时间/μs G通道斜率 G通道截距 B通道曝光时间/μs B通道斜率 B通道截距 145 2.17 50.58 276 2.52 50.74 137 0.84 53.08 364 5.44 52.79 480 4.37 53.10 444 2.72 55.12 545 8.14 54.70 575 5.24 54.06 534 3.27 55.90 表 2简化标定的9个未知数
Table 2.9 unknowns for simplified calibration
$ {K_r} $
(W−1·m2·sr·μs−1)$ {B_r} $
(W−1·m2·sr·μs−1)$ G_r^{noise} $
(DN)$ {K_g} $
(W−1·m2·sr·μs−1)$ {B_g} $
(W−1·m2·sr·μs−1)$ G_g^{noise} $
(DN)$ {K_b} $
(W−1·m2·sr·μs−1)$ {B_b} $
(W−1·m2·sr·μs−1)$ G_b^{noise} $
(DN)0.0149 0.0103 49.07 0.0091 0.0112 47.67 0.0061 0.0070 52.10 表 3计算值与标定值的相对误差
Table 3.Error between calculated and calibrated values
温度(K) 400 μs 500 μs R(%) G(%) B(%) R(%) G(%) B(%) 973.15 −1.11 0.43 −0.22 2.17 −0.57 0.73 1023.15 0.32 0.91 −0.57 3.38 −0.15 −0.40 1073.15 −0.06 2.56 1.01 0.63 0.38 1.10 1123.15 0.78 2.48 −1.14 −1.98 0.28 −0.89 1173.15 −0.05 2.49 0.03 −2.82 0.53 −0.20 1223.15 −0.18 1.09 0.62 1.15 −0.75 −0.83 1273.15 -- 0.23 0.72 -- −0.00 −0.04 1323.15 -- -- −0.45 -- -- −0.03 -
[1] XIE CH Y, SONG J, LIU Y,et al. Design and research on calibration method of multi-channel self-calibration infrared radiation thermometer[J].Proceedings of SPIE, 2021, 12061: 120611M. [2] HU H, SONG P, FENG H,et al. Surface temperatμre of blast fireball measured by colorimetric thermometer[C].Proceedings of the International Conference on Mechatronic System and Measurement Technology, 2012.(查阅网上资料, 未找到本条文献信息, 请确认).HU H, SONG P, FENG H,et al. . Surface temperatμre of blast fireball measured by colorimetric thermometer[C].Proceedings of the International Conference on Mechatronic System and Measurement Technology, 2012.(查阅网上资料, 未找到本条文献信息, 请确认). [3] 李进军. 彩色CCD比色测温的灰度值融合处理方法研究[J]. 计算机测量与控制,2012,20(1):177-179.doi:10.16526/j.cnki.11-4762/tp.2012.01.038LI J J. An intensity fusion method applied to color CCD-based colorimetric temperature measurement[J].Computer Measurement & Control, 2012, 20(1): 177-179. (in Chinese).doi:10.16526/j.cnki.11-4762/tp.2012.01.038 [4] YAN J H, LI W T. Error correction research of colorimetric temperature-measurement based on CCD[C].Proceedings of the 31st Chinese Control Conference, IEEE, 2012: 5649-5652. [5] YAN R, ZHOU X M, LI F. Survey of dual waveband colorimetric temperature measurement technology[C].Proceedings of the 26th Chinese Control and Decision Conference, IEEE, 2014: 5177-5181. [6] 张晓龙, 刘英, 孙强. 高精度非致冷长波红外热像仪的辐射标定[J]. 中国光学,2012,5(3):235-241.ZHANG X L, LIU Y, SUN Q. Radiometric calibration of uncooled long-wave infrared thermal imager with high-precision[J].Chinese Optics, 2012, 5(3): 235-241. (in Chinese). [7] 黄洁, 张轲, 朱晓鹏, 等. 基于RGB数字滤光的CCD 熔覆测温系统的标定[J]. 光电子· ,2013,24(5):967-974.doi:10.16136/j.joel.2013.05.008HUANG J, ZHANG K, ZHU X P,et al. Calibration of CCD temperature measurement system based on RGB digital filtering in laser cladding[J].Journal of Optoelectronics·Laser, 2013, 24(5): 967-974. (in Chinese).doi:10.16136/j.joel.2013.05.008 [8] 毛尹航, 于天河. 高速CCD像机的测温系统标定方法[J]. 哈尔滨理工大学学报,2016,21(1):72-76.doi:10.15938/j.jhust.2016.01.015MAO Y H, YU T H. Calibration method to measure the temperature system based on the high-speed CCD camera[J].Journal of Harbin University of Science and Technology, 2016, 21(1): 72-76. (in Chinese).doi:10.15938/j.jhust.2016.01.015 [9] 马岩, 张帅, 刘元, 等. 基于天基定量实测数据的月球长波红外辐射特性研究[J]. 中国光学,2022,15(3):525-533.doi:10.37188/CO.2021-0202MA Y, ZHANG SH, LIU Y,et al. Lunar long-wave infrared radiation characteristics based on space-based quantitative measured data[J].Chinese Optics, 2022, 15(3): 525-533. (in Chinese).doi:10.37188/CO.2021-0202 [10] 孙志远, 常松涛, 朱玮. 中波红外探测器辐射定标的简化方法[J]. 红外与 工程,2014,43(7):2132-2137.doi:10.3969/j.issn.1007-2276.2014.07.017SUN ZH Y, CHANG S T, ZHU W. Simplifying method of radiance calibration for MWIR detector[J].Infrared and Laser Engineering, 2014, 43(7): 2132-2137. (in Chinese).doi:10.3969/j.issn.1007-2276.2014.07.017 [11] 罗茂捷, 周金梅, 傅景能, 等. 考虑积分时间变量的红外系统辐射响应定标[J]. 红外与 工程,2013,42(1):36-40.doi:10.3969/j.issn.1007-2276.2013.01.007LUO M J, ZHOU J M, FU J N,et al. Integration time as variable for radiometric calibration of infrared system[J].Infrared and Laser Engineering, 2013, 42(1): 36-40. (in Chinese).doi:10.3969/j.issn.1007-2276.2013.01.007 [12] 梁美, 孙博君, 孙晓刚, 等. 多光谱高温计有效波长标定方法研究[J]. 光谱学与光谱分析,2017,37(8):2352-2355.LIANG M, SUN B J, SUN X G,et al. Study on effective wavelength calibration method of multispectral pyrometer[J].Spectroscopy and Spectral Analysis, 2017, 37(8): 2352-2355. (in Chinese).