Mirror 4 is just a flat mirror like Newtonian telescope's secondary mirror, to give convenience for eyes.

镜4只是一块平面镜，就象牛顿式望远镜的副镜一样，方便观测。

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By analyzing the detecting features of seed metering device, a calibration method of camera system that is only composed of a single camera and a flat mirror is proposed.

通过对排种器性能检测的特点分析，提出了由单摄像机和平面镜组成的摄像系统标定方法。

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This paper discusses the accuracy problem of testing a large aperture flat mirror by using stitching interferometry, and analyses the stitching accuracy in theory and experiment.

讨论了在用子孔径拼接法检测大口径光学镜面时的精度问题，并分别从理论上和实验中对拼接检验的精度做了定量分析。

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U.S. regulations require new cars to have a flat mirror on the driver's side.

CNN: Disco ball-inspired mirror gets rid of driver's blind spot

After Ovshinsky allegedly violated their agreement, Manning sued and eventually received control of ECD's X-ray-mirror and flat-panel display technology, which he later sold off.

FORBES: Magazine Article

Hick's mirror has subtle curves, giving the driver a field of view of about 45 degrees, compared with 15 to 17 degrees of view in a flat driver's side mirror.

CNN: Disco ball-inspired mirror gets rid of driver's blind spot