projections投影图projectionn.投影；投射；规划；发射；凸出物；预测；放映projection of crystal晶体投影,晶体的投影projection eomparator投影比长仪projection instrument投影仪,映像器projection on a plane平面投影projection technology投影技术projection welded cap凸焊帽,有凹凸的焊帽projection efficiency投射效率projection generation[计] 投影生成projection simulation投影仿真projection television投影 电视