FLUID BEARING TYPE OPTICAL DEFLECTOR

摘要

PURPOSE:To constitute the optical deflector of a small inclination of a reflecting surface by adopting the constitution consisting of a dynamic pressure bearing part to a large effective diameter and applying a prepressure to the bearing part in a thrust direction by magnets. CONSTITUTION:A dynamic pressure is generated in a radial bearing 1B and a thrust bearing 1A when a revolving shaft 1 and a mirror 6 are rotated in a prescribed rotating direction at a prescribed rotating speed by the motor driving part. The revolving shaft 1 is then supported without contact is radial ad thrust direction by a sleeve 2 and continues to rotate in the state in which the friction load and friction fluctuation are nearly zero. The spacing in the floating state of the thrust bearing 1A is about 1 mum with respect to the effective diameter of a thrust groove a when the attraction force between the 1st and 2nd thrust magnets 13, 14 is adequately set by adjusting the spacing thereof. The surface inclination of the revolving shaft 1 and the mirror 6 fixed thereto is suppressed to submicronorder. The correct thrust bearing support is thus executed even if the entire part of the optical deflector is placed horizontally or vertically upside down.