Pair of telescopic 3D glasses

The utility model discloses a pair of telescopic 3D glasses, which comprises a glasses frame, and two lenses are clamped in the glasses frame; glasses legs are hinged to two ends of the glasses frame;the end parts of the two glasses legs are connected with telescopic pieces; the telescopic piece comprises a shell, a second positioning block is clamped in the middle of an inner cavity of the shell, and a first guide groove is concavely formed in the inner wall of the shell; an adjusting block is arranged in the first guide groove in a sliding manner; a first spring is bound between the adjusting block and the second positioning block; a plurality of positioning holes are formed in the shell in a penetrating manner, and are communicated with the first guide groove; a belt is clamped on theouter wall of the shell, a first positioning block is clamped at the movable end of the belt, and the first positioning block is arranged in the positioning hole in a penetrating mode and abuts against the end of the adjusting