Precise clamping device and pre-tightening method for large-caliber laser transmission reflector

The invention relates to a precise clamping device for a large-caliber laser transmission reflector, which comprises a reflector element, a mirror frame assembly, a mirror body pressing plate, a guidecushion block, a flexible element, flat-end fine-tooth screws, rubber-head screws and the like. The reflector element realizes bottom surface positioning on a boss at the bottom of the mirror frame assembly; four side surfaces of the mirror frame assembly in the circumferential direction are provided with a plurality of stepped holes which are distributed in a triangular array, wherein the largeholes are threaded holes, the small holes are through holes; and after the guide cushion block and the flexible element are sequentially arranged in the through holes, the flat-end fine-tooth screws are screwed into the threaded holes in the side walls to realize the pre-tightening of the reflector element in the circumferential direction; the mirror body pressing plate is arranged on the mirror frame assembly, and the fro