PURPOSE: To ensure continuous compatibility with a change in the degree of far-sightness and near-sightness by constituting a lens body of one convex lens and one concave lens for changing the distance thereof from each other.

CONSTITUTION: A stationary lens 11 is fixed to a glasses frame 10, and a movable lens 9 is laid at the right side thereof. Also, a support shaft 12 is provided on both sides of the movable lens 9. A slender hole section 13 is formed forward of the frame 10, and recess and concave sections 14 and 14 are continuously formed on the upper and lower sides of the hole section 13. The support shaft 12 of the movable lens 9 is inserted in the section 13 and the both ends thereof are provided with a knob 15. The diameter of the shaft 12 is so determined as to be rather tight in the section 13, and fixed in such a way as clamped in an upper section faced to the upper and lower sides of the section 13. The lens 9 can be caused to shift via the operation of the knob 15 by fingers. Also, the lens 9 can be fixed at an intermediate position due to the action of the sections 14.