Abstract: To provide a closing block of the frame wherein the lens can be tightly fixed to the rim without rattling and the installing/removing of the lens can be easily operated even if the process precision of the outer shape of the lens is worse. The locking part 10 provided to the lower end portion 3c of the rim 3 is loosely inserted to the loose insert groove 9f of the locking part 9 that is fixed to the upper end portion 3b of the rim 3, and the locking part 10 is urged toward the upper end portion 3b of the rim 3 by the elastic part 11 that is provided between the bottom wall plate 9d of the locking part 9 and the locking part 10. By the urging force the lens 2 to be inserted to the rim 3 is certainly fixed to the rim 3. Moreover, because the inner shape of the rim 3 is expanded by pulling out the cut 3a of the rim 3 and is shrunk via the elastic part 11 by releasing the cut 3a, the lens 2 can be exchanged without using an exclusive screwdriver.