1.1 本规程描述了照明和观察试样的几何形状以及表征材料外观的光学测量的相应几何形状。它建立了术语、符号、坐标系和功能符号，以描述样品的几何方向、样品的照明（或光学照射）几何形状，以及样品、测量标准或开放采样孔径反射或透射的通量收集几何形状。 1.2 表征回射材料外观的光学测量具有特殊性质，因此在其他ASTM标准中对其进行了处理，不在本规程的范围内。 1.3 直径小于0.5mm的区域的透射光或反射光的测量可能受到光学相干的影响，因此在本实践中不考虑对此类小区域的测量，尽管本实践中描述的基本概念已在该测量领域中采用。 1.4 为了表征外观，测量样品反射或透射特性的方法规范不完整，没有对系统光谱性质的完整描述，但光谱条件不在本规程的范围内。ISO 5/1中描述了使用功能符号来指定光谱条件。 1.5 本标准并不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建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 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》中确立的国际公认标准化原则制定的。 =====意义和用途====== 5.1 本规程适用于外观目视评估或测量设备的制造商和用户、与此类设备相关的编写标准的人员，以及希望详细说明外观观察或测量属性的其他人员。 这种做法的使用使这些规范简洁明了。功能符号便于直接比较观察情况和测量仪器的几何规格。

1.1 This practice describes the geometry of illuminating and viewing specimens and the corresponding geometry of optical measurements to characterize the appearance of materials. It establishes terms, symbols, a coordinate system, and functional notation to describe the geometric orientation of a specimen, the geometry of the illumination (or optical irradiation) of a specimen, and the geometry of collection of flux reflected or transmitted by the specimen, by a measurement standard, or by the open sampling aperture. 1.2 Optical measurements to characterize the appearance of retroreflective materials are of such a special nature that they are treated in other ASTM standards and are excluded from the scope of this practice. 1.3 The measurement of transmitted or reflected light from areas less than 0.5 mm in diameter may be affected by optical coherence, so measurements on such small areas are excluded from consideration in this practice, although the basic concepts described in this practice have been adopted in that field of measurement. 1.4 The specification of a method of measuring the reflecting or transmitting properties of specimens, for the purpose of characterizing appearance, is incomplete without a full description of the spectral nature of the system, but spectral conditions are not within the scope of this practice. The use of functional notation to specify spectral conditions is described in ISO 5/1. 1.5 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. 1.6 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 ====== 5.1 This practice is for the use of manufacturers and users of equipment for visual appraisal or measurement of appearance, those writing standards related to such equipment, and others who wish to specify precisely conditions of viewing or measuring attributes of appearance. The use of this practice makes such specifications concise and unambiguous. The functional notation facilitates direct comparisons of the geometric specifications of viewing situations and measuring instruments.