有效亮度温度测量中发射率影响的修正

经典的短波高温修正模型不适用于中长波红外温度计的发射率修正和不确定度评定。采用有效亮度温度概念,得到了对于温度范围和测温波长具有广泛适用性的发射率影响模型以及具有简明物理含义的微差近似形式,包含了经典亮度温度理论中的发射率影响修正和环境辐射误差修正。定量分析了经典的短波高温修正模型的误差。针对黑体辐射源的不同溯源方法,讨论了辐射温度计校准中的发射率影响修正方法,并给出修正实例。所用方法可用于辐射测温应用、辐射温度计校准和黑体辐射源校准中的发射率和环境影响修正以及辐射源发射率不确定度对校准结果不确定度贡献的计算。     

钨带灯的亮度温度-波长特性及其与结构的关系

在温度量值复现与传递以及国际比对中经常需要对亮度温度进行波长修正.探讨了钨带灯结构与亮度温度模型的关系,计算了T型钨带灯在400～1100 nm亮度温度对波长的导数,并利用实验数据进行了大波长间隔的修正验证.定性分析了不同结构钨带灯与T型钨带灯亮度温度-波长特性的差异.利用钨带灯的亮度温度-波长特性进行波长修正可减小温度量值传递的不确定度,扩展钨带灯应用的光谱范围.     

三波长温度测量方法

对短波段内的发射率函数建立了一种普适性模型,这种普适性发射率模型只需选择三个波长即可构造封闭的温度测量方程,解决了辐射测温中温度与发射率相互耦合的问题,从而实现了实际温度的准确测量。在测量数据处理上,采用分量形式,消除了测量光学系统的影响,使其无需标定且计算简单。     

高稳定度真空钨带灯800℃～1700℃温度范围内不确定度评定

介绍了在2000年度全国大区级法定计量技术机构800℃～1700℃温度比对中,采用标准光学高温计及其本身有效波长,测量指定有效波长下高稳定度真空钨带灯亮度温度的一种更为合理的不确定度评定方法,同时给出评定结果和适用范围。     

多光谱辐射测温理论综述

介绍了多光谱辐射测温理论的研究现状，即多光谱辐射测温法的3种数学模型的建立方法和多波长辐射温度计的8种数据处理方法，并分析了各自的特点。     

二级校准用温度固定点

近年来出现了一种新的温度固定点校准技术。这种新技术不同于经典的固定点技术，所用设备简单，操作方便，工作效率高，主要适用于二级和工业温度计的校准。本文简要介绍了若干应用例子：一种不需用液氮或干冻冻制及杜瓦瓶保存的复现水三相点的新方法，自动金属固定点装置和不锈饮固定点容器及其复现装置等。     

应用辐射技术进行玻璃测温的理论研究

玻璃工业生产过程是辐射测温技术应用最重要的领域之一.给出了实际测温过程等温与非等温两种情况下建立的数学模型.提出了有效深度的概念,将有效温度与表面温度联系起来,通过表面温度的测量确定有效温度,提高玻璃生产过程中温度测量的准确性.文中并指出波长选择在玻璃表面温度测量中的重要性.     

黑体辐射源的多波长有效亮度温度校准和不同溯源方式特点分析

介绍了中国计量科学研究院建立的标准变温黑体辐射源和有效亮度温度比较装置;阐述了黑体辐射源多波长有效亮度温度校准的2种方法,给出典型校准结果并分析了辐射源特性。比较分析了3种溯源方式的性能特点及其应用的影响因素。提出控温复现性的概念,它是以往未被重视的辐射源关键性能参数。多波长有效亮度温度校准是可减小或消除有效发射率和接触测温测点温差影响的溯源方案,与传统溯源方式特性互补,可用于评价辐射源的有效发射率和测点温差,对控温复现性好的辐射源效果最优。     

环境辐射对辐射温度计测量结果的影响

在辐射温度计响应波长一定情况下,主要通过计算环境辐射对黑体辐射温度、发射率不为1辐射温度计的修正值,分析和讨论了在计量检定工作中环境辐射对辐射温度计测量结果的影响大小,并阐述了在结果计算中对它们进行修正的必要性和重要性。     

辐射温度计分度方法探讨

研讨了辐射温度计的标定方法，提出了１种新的标定法－分度函数法；并以Ｇｅ光电池为例，导出其分度函数的具体形式，同时估算了分度误差。     

NIST Radiance Temperature and Infrared Spectral Radiance Scales at Near-Ambient Temperatures

The realization and the dissemination of spectral radiance and radiance temperature scales in the temperature range of −50 to 250°C and spectral range of 3–13 μm at the National Institute of Standards and Technology are described. The scale is source-based and is established using a suite of blackbody radiation sources, the emissivity and temperature of which have been thoroughly investigated. The blackbody emissivity was measured using the complementary approaches of modeling, reflectometry, and the intercomparison of the spectral radiance of sources with different cavity geometries and coatings. Temperature measurements are based on platinum resistance thermometers and on the direct use of the phase transitions of pure metals. Secondary sources are calibrated using reference blackbody sources, a spectral comparator, a controlled-background plate, and a motion control system. Included experimental data on the performance of transfer standard blackbodies indicate the need for development of a recommended practice for their specification and evaluation. Introduced services help to establish a nationwide uniformity in metrology of near-ambient thermal emission sources, providing traceability in spatially and spectrally resolved radiance temperature, spectral radiance, and background-corrected effective emissivity.     

Influence of Non-ideal Blackbody Radiator Emissivity and a Method for its Correction

Demands for accurate temperature measurement and calibration are increasing along with the wider use of radiation thermometry in industry. However, the deviation of a ‘blackbody’ radiator emissivity from the emissivity of an ideal blackbody remains one of the main uncertainty contributions in the calibration of radiation thermometers, although the performance of blackbody radiators has been continually improving. Nevertheless, the influence of this deviation was often ignored due to the complexity of the correction. In this paper, general methods to evaluate the influence of the emissivity deviation of a blackbody radiator from unity for typical radiation thermometer models are described. An approximate practical method for wide-band radiation thermometers is proposed. Moreover, the concept of equivalent wavelength and the corresponding calculation method are introduced to simplify the mathematical model. The calculation result and a mathematical expression for the equivalent wavelength applicable to most popular radiation thermometers with a spectral range of 8–14 μm are given. The analysis and calculation show that the influence of blackbody radiator emissivity on longer working-wavelength radiation thermometer calibrations at mid or high temperatures cannot be ignored.     

100～400K真空红外亮温标准黑体辐射源研制

介绍了中国计量科学研究院研制的100~400K真空红外亮温标准黑体辐射源的工作原理、结构、性能测试方法及测试结果。黑体辐射源通过液氮制冷与3温区控制实现了100~400K范围内的温度控制。在真空环境下,测试了其在温度范围100~400K轴向温度均匀性、底部温度稳定性等技术指标,结果表明均匀性优于0.120K,控温稳定性优于0.020K/20min;在室温大气环境下,利用基于控制环境辐射的发射率测量方法测量了黑体空腔发射率,空腔法向发射率为0.9998。采用基于蒙特卡罗黑体发射率仿真计算方法分析轴向温度均匀性对空腔发射率的影响,分析了标准黑体辐射源的不确定度来源,在8~16 μm波长亮度温度的合成标准不确定度优于0.030K。     

Photoelectric Emission Measurements of Temperature. Effective Wavelength

A method is proposed for determining the effective wavelength by numerical solution of an integral equation for the case of energy analysis of photoelectrons in a retarding field. With use of an FÉU-175M as a temperature sensor and temperature measurement according to dispersion of previously accelerated photoelectrons in the field of an electrostatic lens, values of the effective wavelength lie within the region of values corresponding approximately to a twofold reduction of the retarding field photoelectric current that follows from calculation based on the empirical equation.     

(50～500)cd/m2亮度水平下的光谱辐射亮度标准

介绍了一种使用溴钨标准灯、烟熏MgO漫反射白板、国家光强度副基准及国家色温度副基准建立 (5 0～ 5 0 0 )cd m2 亮度水平下光谱辐射亮度标准 (380～ 780 )nm的方法。解决了彩色监视器、彩色显像管、彩色液晶屏的光谱、色度及亮度测量的计量标准问题。     

The Use of Filtered Radiometers for Radiance Measurement

A methodology for using a calibrated filter radiometer to measure and monitor the spectral radiance of calibration sources is described. An example is presented using the NIST calibration sphere source that is used to support the NASA Earth Observing remote-sensing program.