Some such telescopes were built so that film or some other equipment could be placed inside the tube , or perhaps a bit beyond the upper end , to capture light that had reflected only off the primary mirror 有些这类的望远镜做成制作得可以把胶片等装置安放在镜筒内部或高出镜口一点的位置上，捕捉仅从主镜面反射的光。
Carried on the modal analysis to mirror tube structure and the whole machine , get the inherence frequency and modal shapes of structure system , not only validating the reliability of the structure , but also being advantage to improve 对镜筒结构和整机都进行了模态分析,得出了系统的固有频率和振型,不仅验证了结构的可靠性,还为改善成像仪的动态特性提供了依据。
The paper studied actual method of imc about panoramic aerial camera , and put forward a true _ angle imc method in scanning orientation . the true _ angle imc is independent of scanning velocity , and the demand of drum control system ' s rotational velocity ' s precision is reduced . at last , through experiments , the true _ angle imc was validated 研究了全景相机像移补偿的具体实现方法，提出了相机在摆扫方向上的真角度补偿方法，补偿后的像移误差与摆扫速度无关，从而降低了对镜筒扫描系统的稳速精度要求。
