针对采用直线脉管制冷的超长线列红外焦平面器件杜瓦封装的需求，提出了一种弹性冷链的设计方案。介绍了超长线列焦平面器件及直线脉管制冷机的特点以及对冷链的力学、热学要求，针对超长线列焦平面杜瓦冷链的设计思路、设计方法进行了研究，针对某型号脉管制冷机及典型超长线列探测器的尺寸、工作温度等要求，采用局部弹性冷链方案，通过有限元仿真工具对冷链进行优化设计，使其能够满足设计指标要求。根据设计结果制作了冷链及测试杜瓦，对冷链温差、器件拼接基板温度均匀性及低温形变进行了测试，并通过振动试验对力学可靠性进行了验证。试验结果证明局部弹性冷链设计方案的正确性和可行性。

A design scheme of flexible cold strap according to the requirement of long linear IRFPA packaging was presented in this paper, the characteristics of long linear IRFPA and linear pulse tube cooler were summarized, design ideas and design methods based on the mechanical and thermal requirements of cold strap were proposed. For typical butting substrate size and working temperature, used partial flexible cold strap scheme was used, which was optimized by FEM tool, design requirements was achieved. Test dewar was made according to the design result, temperature difference of cold strap, flatness and temperature uniformity of butting substrate were verified. The test dewar has passed vibration testing. The test results show that the design scheme is correct and feasible.