The present invention relates to a sight improvement device. The purpose of the present invention is to provide a sight improvement device, which is conveniently operated and automatically changes diopters of a lens to train the ciliary muscle of a user. To this end, the sight improvement device comprises: a main body forming openings at areas in which eyeballs are positioned; a plurality of lenses having different diopters; a lens assembly having a lens support for supporting the lenses and installed in the main body to be able to move for arranging one among the lenses at the openings; a lens exchange driving unit driving the lens assembly; a lens exchange transmission unit between the lens assembly and the lens exchange driving unit to transmit the driving force of the lens exchange driving unit to the lens assembly; and a control unit controlling the lens exchange driving unit to sequentially increase or decrease the diopters of the lenses arranged on the openings. In addition, the present invention may select even an iris muscle exercise and a rectus exercise with the ciliary muscle exercise. In the case of training the iris muscle and the rectus, an iris muscle training mode and/or a rectus training mode are/is selected. The iris muscle training is performed by intermittently repeating exposure of light in a blackout state and the rectus training is performed by left/right, upper/lower and rotating exercises of the eyeballs as the light moves. Ocular lens units with different diopters may be prepared and installed in the sight improvement device according to a user selection. The edge of the ocular lens unit is desirably composed of an elastic material for wearability of the user.본 발명은 시력개선장치에 관한 것이다. 본 발명의 목적은 조작이 간편하고 사용자의 설정에 따라 자동으로 렌즈의 디옵터가 변경되어 사용자의 모양체근을 훈련시키는 시력개선장치를 제공하는 것이다. 이를 위해, 본 시력개선장치는 안구가 위치하는 영역에 개구가 형성된 본체와, 서로 다른 디옵터를 갖는 복수의 렌즈와, 상기 복수의 렌즈를 지지하는 렌즈지지체를 가지고 상기 본체에 상기 렌즈들 중 하나가 상기 개구에 배치되도록 이동가능하게 상기 본체에 설치되는 렌즈조립체와, 상기 렌즈조립체를 구동하는 렌즈교체구동부와,