Abstract: An optical scanning device is disclosed that includes a rotary polygon mirror and an air current rectifying mechanism. The air current rectifying mechanism is positioned with a surface that is substantially parallel to an end surface of the rotary polygon mirror. At least one specified condition is satisfied to insure that negative pressure regions are prevented from forming on planar surfaces of the rotary scanning mirror when the scanning mirror is rotated by a scanning motor. In this manner, dust that normally tends to be deposited on the scanner mirror planar surfaces by eddy currents that form as a result of these negative pressure regions is prevented from adhering to the rotary scanning mirror surfaces. Thus, optical performance of the scanning mirror is maintained over time.

Abstract: A rotating multi-faceted mirror of an optical scanning apparatus is disclosed having a plurality of planar reflective surfaces that deflect and scan a light beam incident thereon. Edges, formed as a result of the dihedral angle between adjacent planar reflective surfaces, generate eddy currents which, over time, result in dust being deposited in axially centered regions of the planar reflective surfaces that are used to scan an object by rotating the reflective surfaces about an axis. The reflectance of these regions thus deteriorates over time, causing the scanning beam quality to deteriorate over time. In order to prevent the accumulation of dust in these regions, at a part of each edge corresponding to an axially centered region where a light beam is effectively reflected on the reflective surfaces of the rotating multi-faceted mirror, a notch is formed that passes through the adjacent reflective surfaces that form the edge.

Abstract: An optical scanning device comprises a rotary polygonal mirror which performs deflection scanning of a light beam emitted from a light source; and an annular member which is disposed around the rotary polygonal mirror in proximity thereto and which has a width extending generally in a diameter of the rotary polygonal mirror.

Abstract: A rotating multi-faceted mirror of an optical scanning apparatus is disclosed having a plurality of planar reflective surfaces that deflect and scan a light beam incident thereon. Edges, formed as a result of the dihedral angle between adjacent planar reflective surfaces, generate eddy currents which, over time, result in dust being deposited in axially centered regions of the planar reflective surfaces that are used to scan an object by rotating the reflective surfaces about an axis. The reflectance of these regions thus deteriorates over time, causing the scanning beam quality to deteriorate over time. In order to prevent the accumulation of dust in these regions, at a part of each edge corresponding to an axially centered region where a light beam is effectively reflected on the reflective surfaces of the rotating multi-faceted mirror, a notch is formed that passes through the adjacent reflective surfaces that form the edge.

Abstract: An optical scanning device is disclosed that includes a rotary polygon mirror and an air current rectifying mechanism. The air current rectifying mechanism is positioned with a surface that is substantially parallel to an end surface of the rotary polygon mirror. At least one specified condition is satisfied to insure that negative pressure regions are prevented from forming on planar surfaces of the rotary scanning mirror when the scanning mirror is rotated by a scanning motor. In this manner, dust that normally tends to be deposited on the scanner mirror planar surfaces by eddy currents that form as a result of these negative pressure regions is prevented from adhering to the rotary scanning mirror surfaces. Thus, optical performance of the scanning mirror is maintained over time.

Abstract: An optical scanning device comprises a rotary polygonal mirror which performs deflection scanning of a light beam emitted from a light source; and an annular member which is disposed around the rotary polygonal mirror in proximity thereto and which has a width extending generally in a diameter of the rotary polygonal mirror.