An endoscope includes a control device, a movable joint and a detecting head, wherein the control device comprises a controller, a plurality of control lines and a protective tube, one end of the protective tube is connected to the controller, and the other end is connected to be made a bent movable joint, and the control lines are disposed therein； the control lines are connected to the controller at one end, and the movable joint is connected at the other end, and the movable joint can be pulled when the user controls the controller to pull the control lines； The control device includes a tubular adjusting member sleeved on the outside of the protective tube, and the adjusting member and the protective tube are threadedly engaged. When the user rotates the adjusting member, the protective tube can be driven to move along the axial direction, thereby changing the protection. The length between the tube and the controller to the movable joint allows the tightness of the control lines located within the sheath to be adjusted.一種內視鏡包括有一控制裝置、一活動關節與一探測頭，其中，控制裝置包括有一控制器、多數條控制線與一護管，護管的一端連接至控制器，另一端連接於可做彎折的活動關節，且該些控制線穿設於其中；該些控制線一端連接控制器，另一端則連接活動關節，當使用者操控控制器拉動該些控制線時可以拉動活動關節；另外該控制裝置包括一管狀的調整件套設於該護管外部，且調整件與護管之間以螺紋配合，當使用者轉動調整件時，可驅使護管沿著軸向移動，進而改變護管與控制器至活動關節之間的長度，使位於護管內的該些控制線的鬆緊程度可以被調整。
