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影院座位设计 下图为影院的剖面示意图，座位的满意程度主要取决于视角α和仰角β．视角α是观众眼睛到屏幕上、下边缘视线的夹角，α越大越好；仰角β是观众眼睛到屏幕上边缘视线与水平线的夹角，β太大使人的头部过分上仰，引起不舒适感，一般要求β不超过30°． 记影院屏幕高h，上边缘距地面高H，地板线倾角θ，第一排和最后一排座位与屏幕水平距离分别为d和D，观众平均坐c(指眼睛到地面的距离)．已知参数h=1.8，H=5，d=4.5，D=19，c=1.1(单位：m)．
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