periscope

Submarines are most vulnerable to detection when the submarine commander uses a periscope to assess the situation on the surface..当潜艇指挥官使用潜望镜对海面态势进行评估的时候最容易被探测到也最容易被攻击。

The radar affords the helicopter long-range search, imaging, and tracking capabilities for surface vessels and includes an advanced periscope detection mode..该雷达可为直升机提供远程水面舰艇的搜索、成像、跟踪能力，包括先进的潜望镜检测模式。

In that sense, Internet use is like a periscope: When users age 50-plus put theirs up, researchers have found, they’re looking both backward and forward, toward the past and the future..在这个意义上，互联网的使用像潜望镜：当使用者年龄50余岁时，研究人员已经发现，他们也在向后和向前的寻找，面向过去和未来。