银幕的宽度、挂高、亮度，以及放映机的光通量、焦距等都是电影观众厅设计的重要因素。

The width, height, brightness of the screen and the luminous flux, focus of the cineprojector are important factors of cinema auditorium design.

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大视场光学系统由于非共轴、视场、焦距等因素的影响，光学设计比较复杂，光学系统的畸变比较大。

Optical systems with large FOV are usually complex in design and have large distortion due to such factors as eccentric, field of view, and focal length.

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戴眼镜看物体与眼睛直接看物体时相比，物体究竟变小、等大还是变大，取决于眼镜与眼睛光心之距与眼睛的焦距。

Comparing to see the objects with glasses, with seeing them directly will become bigger, equal or small all depends on focal distance between glasses and eyes.

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