GB/T 20494.2-2006
ActiveMicrographics — Quality control of COM recorders that generate images using a single internal display — Part 2: Method of use
缩微摄影技术 使用单一内显示系统生成影像的COM记录器的质量控制 第2部分:使用方法
Catalogue
前言 → 引言 → 1 范围 → 2 规范性引用文件 → 3 术语和定义 → 4 方法的概述 → 5 测试程序 → 6 第一代缩微品的密度 → 7 测试方法 Foreword → Introduction → 1 Scope → 2 Normative References → 3 Terms and Definitions → 4 Overview of the method → 5 Test procedure → 6 Density of first-generation microforms → 7 Test methods
Scope
This part of GB/T 20494 specifies the method of use of the software test target specified in GB/T 20494.1-2006.
GB/T20494的本部分规定了GB/T20494.1-2006所规定的软件测试标板的使用方法
Normative References
Keywords
Application Summary AI generated
Operators, quality control personnel, and engineers in micrographics use this standard to establish and monitor the quality baseline of images produced by COM recorders. It provides a systematic test procedure to ensure consistency and reliability of microforms. This standard matters because it helps optimize key parameters like exposure, density, and resolution, ensuring that microfilm images meet required specifications and remain usable over time.
该标准由COM记录器的操作人员、质量管理人员以及缩微摄影技术领域的工程师使用。他们用它来建立和监控COM系统输出影像的质量基准，确保缩微品的一致性和可靠性。该标准重要，因为它提供了系统化的测试方法，帮助用户优化曝光、密度和解像力等关键参数，从而保证缩微影像的长期可用性和符合规范。
AI Summary AI generated
GB/T 20494.2-2006, identical to ISO 14648-2:2001, specifies the quality control method for COM recorders that generate images using a single internal display, focusing on the use of software test targets. The standard covers test procedures including determination of optimum exposure, density, reduction ratio, and resolution, as well as density requirements for first-generation microforms and test methods. It provides systematic guidance for installation, maintenance, and routine inspection of COM systems, ensuring consistent and reliable microimage quality.
GB/T 20494.2-2006等同采用ISO 14648-2:2001，规定了使用单一内显示系统生成影像的COM记录器的质量控制方法，重点描述了软件测试标板的使用步骤。标准涵盖测试程序，包括确定最佳曝光量、密度、缩率、解像力等参数，以及第一代缩微品的密度要求和测试方法。该标准为COM系统的安装维护和常规检测提供了系统化指南，确保缩微影像质量的一致性和可靠性。
Key Sentences extracted from text
标板的基本用途宜是建立一个工作质量基准，然后用它作为定期监测性能一致性的手段。
标板的最佳曝光量应能使EHN、OCR-B或替代字型的影像中最窄线宽的字符显得曝光不足，最宽线宽的字符显得曝光过度。
COM记录器的缩率应使用标板1的边界或标板2的测量标尺来确定。
应根据可分辨的最小的即最细的测试图案来确定解像力，观察时使用的显微镜的最低放大倍率应等于缩微影像所用的缩率。
表1给出了用具有ISO 5-3所规定的光谱条件和ISO 5-2所规定的几何条件的密度计所测得的漫透射视觉密度，即M状态蓝密度的推荐值。
The basic purpose of the test target should be to establish a working quality baseline, and then use it as a means of regularly monitoring performance consistency.
The optimum exposure of the target should be such that the characters with the narrowest line width in the EHN, OCR-B or substitute font appear underexposed, and those with the widest line width appear overexposed.
The reduction ratio of the COM recorder should be determined using the boundaries of target 1 or the measuring scale of target 2.
The resolution should be determined from the smallest, i.e. finest, test pattern that can be resolved, and the minimum magnification of the microscope used for observation should be equal to the reduction ratio used for the microimage.
Table 1 gives recommended values for diffuse transmission visual density, i.e. M-state blue density, measured with a densitometer having the spectral conditions specified in ISO 5-3 and the geometric conditions specified in ISO 5-2.