A displacement measuring device is disclosed. The displacement measuring device is applied to a tissue and includes a loading component, a press component and a force sensing module. The press component presses on the tissue directly or indirectly. The force sensing module includes at least a force-deformation element disposed between the loading component and the press component. When the tissue displaces, the loading component receives an external force and then the displacement of the tissue is computed by the force sensing module through sensing the force-deformation element. A displacement measuring method and a radiotherapy assist system are disclosed as well. The device and method in accordance with the present invention are applied to sense the change of the force rather than monitor a target optically so as to provide a noninvasive and more accurate displacement measuring technique.一種位移量測裝置,應用於一組織,且位移量測裝置包括一負載部材、一抵壓部材以及一力量感測模組。抵壓部材係直接或間接抵壓於組織。力量感測模組至少具有一受力反應元件,且受力反應元件設置於負載部材及抵壓部材之間。當組織位移時,負載部材接受一外力,且力量感測模組透過感測受力反應元件,計算組織的位移量。本發明另外揭露一種位移量測方法及一種放射治療輔助系統。本發明之裝置及方法透過感測力量變化,取代習知的光學監視,提供一種非侵入且準確的位移量測技術。1...位移量測裝置11...負載部材12...抵壓部材13...力量感測模組131...受力反應元件132...殼體
