Peripheral ring few-point clamping frame and clamping method for large-diameter plane mirror

The invention relates to a peripheral ring few-point clamping frame and clamping method for a large-diameter plane mirror, and belongs to the technical field of precision optical machines. The clamping frame comprises a frame body, a positioning element, a pressing frame and a clamping element, the frame body is used for installing and clamping the mirror, the tail end of the positioning element abuts against the mirror to position the mirror, the pressing frame is used for limiting the mirror from being disengaged from the frame body, the side face and the front face of the mirror are clamped by changing the distance between the clamping element and the mirror, the front face and the side face of the mirror are respectively clamped by means of the clamping element and the positioning element, a side face center line point clamping mode is adopted, the influence of a clamping force on additional distortion of the surface shape of the mirror is reduced, low stress of clamping on the surface shape of the mirror