圆柱形黑体腔热辐射及其在光纤中的传输

分析了圆柱形黑体腔腔内视在发射率的分布及腔体发射率，讨论了斜光线在光纤中的耦合与传输，并导出了光纤中传输的辐射功率表达式和光电探测器输出电流表达式。探测器输出电流的表达式表明，光电流的大小除随黑体腔温度变化外，还与探测器的下限、上限截止波长有关。下限、上限截止波长的间隔愈大，则光电流愈大，故在接收辐射功率时，探测器前不加窄带滤波片。文中还给出了光电流随温度变化的理论曲线和实验曲线，两者基本吻合。

Thermal Radiation of Cylindrical Enclosure and its Transfer along the Optical Fibre

Considerations are given to the distribution of apparent emissivity along the innersurface of the cylindrical enclosure and the emissivity of the hole. The coupling and the transferof the oblique ray in the optical fibre are discussed,from which the expressions of the radiantenergy and the output current of the photoelectric detector are derived. The expression of theoutput current indicates that the photoelectric current is related not only to the temperaturechange of the blackbody enclosure,but also to the lower and upper limit of the detector wavelength. The wider the gap of the wavelength between the lower and upper limit the bigger thephotoelectric current. A narrow--band pass filter is therefore not needed before the detectorwhile the radiant energy is received by the detector. The theoretical and experimental curves ofthe photoelectric current which vary with the temperature are provided in the article and theexperimental one fits well with the theoretical one. The error between the curves is analysedbriefly and its correction is given. Finally,the general requirments in the design of the blackbody optical fibre temperature sensor probe are presented.