中文摘要：

本文从理论上分析了γ射线相机噪声的主要来源，并在能量分别为0.2 M eV和1.25 M eV γ射线源上标定不同辐照剂量条件下的噪声功率谱。研究结果表明，噪声主要由MCP像增强器增益起伏引起，在空间频率约为0.6331 mm －1处相对强度较强，该峰值在0.2 M eV和1.25 M eV γ射线辐照条件下基本保持不变，噪声功率谱为圆形对称分布，其强度随空间频率增大而快速减小。

英文摘要：

In this paper ,the theoretical analysis was presented on the major source of the noise in the γ‐ray camera .Based on the analysis ,the noise pow er spectrum of theγ‐ray camera was calibrated under γ‐ray radiation sources （0.2 MeV and 1.25 MeV energy ,respectively） of various irradiation dosages .The results show that the noise is mainly induced by the fluctuation of the gain of the MCP image intensifier . The remarkable noise peak occurs nearby the spatial frequency of 0.633 1 mm -1 .And almost the same phenomena are found with both 0.2 MeV and 1.25 MeV radiation energy .Be‐sides ,the noise power spectrum is in circular symmetrical distribution ,whose intensity rapidly decreases with the increase of the spatial frequency .