Abstract: A light beam deflecting device having therein a rotor portion fixed on an outer circumference of a bearing, a polygon mirror stuck and fixed on a supporting section of the rotor portion and an elastic material for pressing and holding the polygon mirror on the supporting section, wherein the rotor portion has a cylindrical portion fixed on the outer circumference of the bearing, the supporting section and a disc-shaped flange portion provided on an end portion of the cylindrical portion, and a clearance is provided between an inner circumference of the cylinder portion on the end portion side where the flange portion is provided and an outer circumference of the bearing.

Abstract: An optical deflection device includes a rotor unit having a rotary polygon mirror and a magnet, a dynamic pressure bearing having a rotary bearing member rotatably supporting the rotor unit and a stationary bearing member, and a stator unit having a base member for supporting the stationary bearing member and a magnet coil for driving the rotary unit in cooperation with the magnet. The optical deflection device further includes a stabilizing member for rectifying and stabilizing airflow caused by the rotation of the rotary polygon mirror, which is mounted on the top of the base member in such a way that the stabilizing member is located close to the mirror surface on the outer periphery of the rotary polygon mirror.

Abstract: There is provided a polygon mirror comprising a mirror body shaped in a regular polygon and having circumferential surfaces, a top surface and a bottom surface, a reflection surface formed on each of the circumferential surface, a machining reference surface provided on one of the top and bottom surfaces, machined to form a mirror surface and used as a reference surface for machining the reflection surface on each of the circumferential surfaces and an assembling reference surface provided on one of the top an bottom surfaces, shaped in parallel to the machining reference surface, machined to form a rough surface and used as a reference surface for assembling the polygon mirror. The polygon mirror has a high degree of reliability in terms of stable optical characteristic when a polygon mirror and a flange member are bonded with each other.

Abstract: An optical deflection device having: a rotor unit including a rotary polygon mirror having a plurality of mirror surfaces on the side surface portion and a holding member holding the polygon mirror; an air dynamic pressure bearing including a rotary bearing member to support the rotor unit and a fixed bearing member rotatably supporting the rotary member; and a stator unit which supports the fixed bearing member, including a winding coil oppositely arranged to the magnet, wherein prior to an assembly process, the adhesive agent layer is formed between the outer peripheral surface of the rotary bearing member and the inner peripheral surface of the holding member, the holding member and the rotary bearing member are set at the following condition, (the inner diameter of the holding member before the assembling)?(the outer diameter of the rotary bearing member before the assembling).

Abstract: There is provided a polygon mirror comprising a mirror body shaped in a regular polygon and having circumferential surfaces, a top surface and a bottom surface, a reflection surface formed on each of the circumferential surface, a machining reference surface provided on one of the top and bottom surfaces, machined to form a mirror surface and used as a reference surface for machining the reflection surface on each of the circumferential surfaces and an assembling reference surface provided on one of the top an bottom surfaces, shaped in parallel to the machining reference surface, machined to form a rough surface and used as a reference surface for assembling the polygon mirror. The polygon mirror has a high degree of reliability in terms of stable optical characteristic when a polygon mirror and a flange member are bonded with each other.

Abstract: A light beam deflecting device having therein a rotor portion fixed on an outer circumference of a bearing, a polygon mirror stuck and fixed on a supporting section of the rotor portion and an elastic material for pressing and holding the polygon mirror on the supporting section, wherein the rotor portion has a cylindrical portion fixed on the outer circumference of the bearing, the supporting section and a disc-shaped flange portion provided on an end portion of the cylindrical portion, and a clearance is provided between an inner circumference of the cylinder portion on the end portion side where the flange portion is provided and an outer circumference of the bearing.

Abstract: An optical deflection device includes a rotor unit having a rotary polygon mirror and a magnet, a dynamic pressure bearing having a rotary bearing member rotatably supporting the rotor unit and a stationary bearing member, and a stator unit having a base member for supporting the stationary bearing member and a magnet coil for driving the rotary unit in cooperation with the magnet. The optical deflection device further includes a stabilizing member for rectifying and stabilizing airflow caused by the rotation of the rotary polygon mirror, which is mounted on the top of the base member in such a way that the stabilizing member is located close to the mirror surface on the outer periphery of the rotary polygon mirror.

Abstract: An optical deflection device having: a rotor unit including a rotary polygon mirror having a plurality of mirror surfaces on the side surface portion and a holding member holding the polygon mirror; an air dynamic pressure bearing including a rotary bearing member to support the rotor unit and a fixed bearing member rotatably supporting the rotary member; and a stator unit which supports the fixed bearing member, including a winding coil oppositely arranged to the magnet, wherein prior to an assembly process, the adhesive agent layer is formed between the outer peripheral surface of the rotary bearing member and the inner peripheral surface of the holding member, the holding member and the rotary bearing member are set at the following condition, (the inner diameter of the holding member before the assembling)≧(the outer diameter of the rotary bearing member before the assembling).

Abstract: A light-beam deflecting apparatus is provided in which a polygon mirror is pushed against a flange to hold it stationary. The light-beam deflecting apparatus includes a base member; a polygon mirror rotatable with respect to the base member; a flange contacting the polygon mirror to hold the polygon mirror; and a pushing member to push the polygon mirror against the flange. One or both of contacting surfaces of the polygon mirror and the flange is/are finished to a surface roughness of Ry, which fulfills a first formula of Ry>3 &mgr;m or a second formula of 3 &mgr;m≦Ry≦20 &mgr;m.

Abstract: The invention concerns light-beam deflecting apparatus in which a polygon mirror is pushed against a flange to hold it stationary. The light-beam deflecting apparatus includes a base member; a polygon mirror being rotatable in respect to the base member; a flange contacting the polygon mirror to hold the polygon mirror; and pushing member to push the polygon mirror against the flange. One or both of contacting surfaces of the polygon mirror and the flange is/are finished to a surface roughness of Ry, which fulfills a first formula of Ry≧3 &mgr;m or a second formula of 3 &mgr;m≦Ry≦20 &mgr;m.

Abstract: A rotary apparatus includes: a radial fixed member; a rotary unit rotatably supported on the radial fixed member; a radial dynamic pressure bearing portion at which the radial fixed member faces the rotary unit; and dynamic pressure generating grooves formed on the radial dynamic pressure bearing portion. The dynamic pressure generating grooves are asymmetrically formed with respect to a rotary axis of the rotary unit.