OPTICAL DEFLECTION SCANNER HAVING A DYNAMIC PRESSURE BEARING

摘要

PROBLEM TO BE SOLVED: To provide an optical deflection scanner which surely holds the oil in a dynamic pressure bearing by suppressing the overflowing and splashing of lubricating fluid, such as oil, during high-speed rotation of a polyhedral mirror member and with which a rotating effect stable for a long period of time may be obtained. SOLUTION: The optical deflection scanner consisting of a revolving shaft which is rotationally driven by a drive motor, a sleeve which holds the revolving shaft through the fluid, a shallow groove for generating dynamic pressure which is disposed at either of the revolving shaft or the sleeve and an oil sump which is formed on a sleeve aperture side is constituted by disposing a sintered metallic annulus in the oil sump formed on the sleeve aperture side and forming surfaces which obviate the penetration of the oil on the inner peripheral surface of the annulus and its periphery.