1.1 本试验方法包括测量透明有机塑料折射率的程序。 1.2 提出了一种折射计方法。该程序将令人满意地涵盖此类材料的折射率范围。折射率测量需要具有均匀折射率的光学均匀样品。 注1: 本试验方法与ISO 489在技术上等同。 1.3 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。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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====== 4.1 本试验方法测量了物质的基本特性，该特性有助于控制纯度和成分，以便于识别，并用于光学零件设计。此测试方法能够读取小数点右侧四位数字。

1.1 This test method covers a procedure for measuring the index of refraction of transparent organic plastic materials. 1.2 A refractometer method is presented. This procedure will satisfactorily cover the range of refractive indices found for such materials. Refractive index measurements require optically homogeneous specimens of uniform refractive index. Note 1: This test method and ISO 489 are technically equivalent. 1.3 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. 1.4 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 This test method measures a fundamental property of matter which is useful for the control of purity and composition for simple identification purposes, and for optical parts design. This test method is capable of readability to four figures to the right of the decimal point.