visual detection
| screening range
| visual detection | |
| chem. | 目测 |
| space | 目视探测 |
| screening range | |
| mil., air.def. | 屏蔽距离 |
| |||
| 目测法 | |||
| 目视探测 | |||
| 图像信号检测 | |||
|
visual detection : 4 phrases in 4 subjects |
| Air defense | 1 |
| Aviation | 1 |
| Electronics | 1 |
| Metallurgy | 1 |