Abstract: An optical scanning element includes: a first member which is constituted of a mirror portion, a mirror supporting portion and a frame portion; a second member which fixes and holds the frame portion of the first member thereon; and a piezoelectric body. The frame portion includes a beam portion and fixing portions which are positioned at both ends of the beam portion, the mirror supporting portion is connected to the beam portion at a connection point, and the piezoelectric body is fixedly mounted on the frame portion in a state that the piezoelectric body extends toward the connection point of the beam portion from the fixing portion to a position not over the connection point thus extending over the beam portion and the fixing portion. Due to such constitution, a swinging angle of the mirror portion can be increased thus enlarging a scanning angle.

Abstract: An optical scanning element includes: a first member which is constituted of a mirror portion, a mirror supporting portion and a frame portion; a second member which fixes and holds the frame portion of the first member thereon; and a piezoelectric body. The frame portion includes a beam portion and fixing portions which are positioned at both ends of the beam portion, the mirror supporting portion is connected to the beam portion at a connection point, and the piezoelectric body is fixedly mounted on the frame portion in a state that the piezoelectric body extends toward the connection point of the beam portion from the fixing portion to a position not over the connection point thus extending over the beam portion and the fixing portion. Due to such constitution, a swinging angle of the mirror portion can be increased thus enlarging a scanning angle.

Abstract: A method for preparing a glass substrate for magnetic recording mediums comprises the steps of lapping a glass substrate, then chemically treating the glass substrate for strengthening to form a strengthening layer having a thickness of not less than 20 &mgr;m and polishing the chemically strengthened glass substrate so that not less than 10 &mgr;m of the strengthening layer on the main face is removed, while leaving not less than 10 &mgr;m of the strengthening layer on the main surface of the glass substrate. The method for preparing a glass substrate for magnetic recording mediums permits the easy preparation of such glass substrates having excellent flatness and excellent surface smoothness and also permits the marked improvement of the rate of machine operation and production efficiency.