1.1 本指南旨在使用户能够使用NIST标准参考材料校正拉曼光谱仪的相对光谱强度响应函数 2. 在224X系列中（当前为SRM 2241、2242、2243、2244、2245、2246），或校准的辐照度源。这种相对强度校正程序将能够对从不同仪器、激发波长和实验室获得的拉曼光谱进行相互比较。 1.2 以国际单位制表示的数值应视为标准。本标准不包括其他计量单位。 1.3 由于与使用激光相关的重大危险，应将ANSI Z136.1或适当的地区标准与此做法结合起来使用。 1.4 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 4.1 通常，使用基于光栅的色散或傅里叶变换拉曼光谱仪测量的拉曼光谱尚未针对仪器响应（检测系统的光谱响应度）进行校正。用不同仪器获得的拉曼光谱可以显示样品化合物的测量相对峰值强度的显著变化。 这主要是由于它们与波长相关的光传输和检测器效率的差异。当使用广泛不同的激光激发波长时，这些变化可能特别大，但当使用相同的激光激发并且在仪器之间比较相同化合物的光谱时，可能发生这些变化。如图所示 图1 ，其显示了SRM 2241的未校正的发光光谱，该光谱是在以785nm激光激发操作的四个不同的市售拉曼光谱仪上获得的。部件更换或维修工作完成后，同一仪器也可能发生仪器响应变化。由于滤波器、光栅、收集光学器件和探测器响应的独特组合，每个光谱仪都具有非常独特的光谱响应。 依赖于光谱仪的光谱响应当然也会影响在这些系统上获得的拉曼光谱的形状。这种响应的形状不应被解释为“好或坏”，而是光谱仪制造商设计考虑的结果。例如，如中所示 图1 ，光谱覆盖范围在光谱仪系统之间可以有相当大的变化。这通常是光谱仪设计中的一种深思熟虑的权衡，其中为了提高光谱分辨率而牺牲了光谱覆盖范围。 图1 SRM 2241在四台利用785nm激发的商用拉曼光谱仪上测量 4.2 光谱峰值强度的变化主要可以通过拉曼强度（y）轴的校准来校正。拉曼光谱仪光谱响应的传统校准方法是通过使用国家计量研究所（NMI），例如NIST，可追踪校准辐照度源。 这种灯有一个定义的强度与波长的光谱输出，其使用程序已经公布( 1. ) 5. 然而，使用白色光源进行强度校准可能会带来实验困难，尤其是对于常规分析工作。经过校准的卤钨灯寿命有限，需要定期重新校准。这些灯通常安装在积分球中，以消除偏振效应并提供均匀的光源辐照度。在实践中，这些源可能很难与拉曼光谱仪的各种采样安排相一致，尤其是在危险区域持续存在电气安全问题的基于显微镜的系统和过程拉曼分析仪。标准灯的优点是它可以用于多种激发波长。 4.3 可以使用校准的拉曼光谱仪对通过照射发光的材料的光谱进行相对发光强度的校正，该相对发光强度是发射波长的函数。可追溯到SI的辐照度源可用于校准光谱仪。几个小组已经提出了这些转移标准来校准拉曼和荧光光谱仪( 1- 6. ). 使用发光玻璃材料的优点是使用拉曼激发激光器来激发发光发射，并且在与样品相同的位置测量该发射。这些玻璃可以用于各种采样配置，并且不需要额外的仪器。眼镜是可拍照的，与主要校准源不同，可能不需要定期重新校准。 NIST提供了一系列荧光玻璃，可用于校准拉曼光谱仪的强度轴。每个玻璃都提供了一个数学方程，该方程是对校正后的发射的描述。操作员将这种数学关系与他们的光谱仪上的玻璃测量值相结合，以产生系统校正曲线。 4.4 本指南描述了使用校准标准源或NIST SRM为拉曼光谱仪生成相对强度校正曲线所需的步骤，以及验证校正的方法。

1.1 This guide is designed to enable the user to correct a Raman spectrometer for its relative spectral-intensity response function using NIST Standard Reference Materials 2 in the 224X series (currently SRMs 2241, 2242, 2243, 2244, 2245, 2246), or a calibrated irradiance source. This relative intensity correction procedure will enable the intercomparison of Raman spectra acquired from differing instruments, excitation wavelengths, and laboratories. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 Because of the significant dangers associated with the use of lasers, ANSI Z136.1 or suitable regional standards should be followed in conjunction with this practice. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 4.1 Generally, Raman spectra measured using grating-based dispersive or Fourier transform Raman spectrometers have not been corrected for the instrumental response (spectral responsivity of the detection system). Raman spectra obtained with different instruments may show significant variations in the measured relative peak intensities of a sample compound. This is mainly as a result of differences in their wavelength-dependent optical transmission and detector efficiencies. These variations can be particularly large when widely different laser excitation wavelengths are used, but can occur when the same laser excitation is used and spectra of the same compound are compared between instruments. This is illustrated in Fig. 1 , which shows the uncorrected luminescence spectrum of SRM 2241, acquired upon four different commercially available Raman spectrometers operating with 785 nm laser excitation. Instrumental response variations can also occur on the same instrument after a component change or service work has been performed. Each spectrometer, due to its unique combination of filters, grating, collection optics and detector response, has a very unique spectral response. The spectrometer dependent spectral response will of course also affect the shape of Raman spectra acquired upon these systems. The shape of this response is not to be construed as either “good or bad” but is the result of design considerations by the spectrometer manufacturer. For instance, as shown in Fig. 1 , spectral coverage can vary considerably between spectrometer systems. This is typically a deliberate tradeoff in spectrometer design, where spectral coverage is sacrificed for enhanced spectral resolution. FIG. 1 SRM 2241 Measured on Four Commercial Raman Spectrometers Utilizing 785 nm Excitation 4.2 Variations in spectral peak intensities can be mostly corrected through calibration of the Raman intensity (y) axis. The conventional method of calibration of the spectral response of a Raman spectrometer is through the use of a National Metrology Institute (NMI), for example, NIST, traceable calibrated irradiance source. Such lamps have a defined spectral output of intensity versus wavelength and procedures for their use have been published ( 1 ) 5 . However, intensity calibration using a white-light source can present experimental difficulties, especially for routine analytical work. Calibrated tungsten halogen lamps have a limited lifetime and require periodic recalibration. These lamps are often mounted in an integrating sphere to eliminate polarization effects and provide uniform source irradiance. In practice, these sources can be difficult to align with the variety of sampling arrangements that are now typical with Raman spectrometers, especially microscope based systems and process Raman analyzers where electrical safety concerns persist in hazardous areas. The advantage of a standard lamp is that it can be used for multiple excitation wavelengths. 4.3 The spectra of materials that luminesce with irradiation can be corrected for relative luminescence intensity as a function of emission wavelength using a calibrated Raman spectrometer. An irradiance source, traceable to the SI, can be used to calibrate the spectrometer. Several groups have proposed these transfer standards to calibrate both Raman and fluorescence spectrometers ( 1- 6 ). The use of a luminescent glass material has the advantage that the Raman excitation laser is used to excite the luminescence emission and this emission is measured in the same position as the sample. These glasses can be used in a variety of sampling configurations and they require no additional instrumentation. The glasses are photostable and unlike primary calibration sources, may not require periodic recalibration. NIST provides a series of fluorescent glasses that may be used to calibrate the intensity axis of Raman spectrometers. A mathematical equation, which is a description of the corrected emission, is provided with each glass. The operator uses this mathematical relation with a measurement of the glass on their spectrometer to produce a system correction curve. 4.4 This guide describes the steps required to produce a relative intensity correction curve for a Raman spectrometer using a calibrated standard source or a NIST SRM and a means to validate the correction.