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目的：用系统均匀性指标检测准直器的质量。材料和方法：同型号低能通用及同型号低能高分辨平行孔准直器各４ 只，用ＮＥＭＡ标准（１９９４）中固有泛源均匀性的方法分别测试带准直器的系统均匀性，同时测试系统空间分辨率及灵敏度，对测试结果进行比较和分析。结果：同一型号准直器的系统空间分辨率与灵敏度两项指标基本接近， 而均匀性指标存在较大差异（当部分准直器存在质量问题时）。其中系统积分和微分均匀性分别超过６％ 和３％ 的３ 只准直器被证实存在质量问题。结论：均匀性测试能定量和定性地反映准直器的性能。能有效地反映准直器的质量问题。
Objective: To detect the collimator’s quality with system uniformity index. MATERIALS AND METHODS: Four of the same type of low energy universal and same type low energy high resolution parallel hole collimators were used to test the system homogeneity with collimator respectively by the method of inherent homogeneity in NEMA standard (1994) System spatial resolution and sensitivity, the test results were compared and analyzed. Results: The two models of spatial resolution and sensitivity of the same type of collimators are basically close to each other, while the homogeneity indexes are quite different (when some collimators have quality problems). Three collimators, of which system integration and differential uniformity exceeded 6% and 3%, respectively, were found to have quality problems. Conclusion: The uniformity test can quantitatively and qualitatively reflect the performance of the collimator. Can effectively reflect the collimator quality problems.