A scanning system, including a main housing, and at least one optical wedge (12) rotatable about a shaft means (40) located within the main housing (26), wherein a laser beam having an optical axis and incident on the optical wedge (12), is refracted at least once by the wedge; characterized in that the shaft means (40) passes through the center of the at least one wedge (12) and that the optical axis of the incident laser beam is substantially parallel to, but laterally offset from, the shaft means (40).