星座的俯角降到了地平线以下。

The depression of the constellation fell below the horizon.

但须注意，不应用极度的俯角或仰角。

But should note that no application of extreme bow Angle or elevation.

本文首先讨论汽车平视显示器(HUD)中，显示图象的感觉和俯角之间的关系。

First this paper discusses the relation between perception of displayed image and Angle of depression in automotive Head_Up Displays (HUDs).