The amount of sky that you can view through a telescope is called the real (true) fieldofview and is measured in degrees of arc (angularfield).
通过望远镜你所能看到的天空的范围称作真实视场，以弧度值(角视场)来度量。
2
The antenna is capable of acquiring the range and angular information of all obstacles in its field-of-view simultaneously without using a scanning or switching antenna.