monocular

The images you see are only half as bright as they would be with a traditional monocular eyepiece.

你看到的图像，和用传统单眼目镜看到的图像相比，亮度只有一半。

He watches television, mostly sports, with a monocular.

他用一个单筒望远镜看电视，主要是看体育节目。