| 摘要 |
A self-acting gas bearing, which may include a grooveless design, that effects smooth and precise rotation of a load over an extended series of start/stop cycles, includes a beam scanner using a self-acting gas bearing to support a beam deflector preferably in the form of a holographically-generated planar diffraction grating disk (i.e., a hologon). The contemplated gas bearing is designed to operate either vertically or tilted at an angle by use of a bottom grooved thrust plate to provide vertical lift. The weight of the rotor assembly, which includes the hologon and other components, is reduced (i.e., unweighted) by use of opposing magnets. The frictional degradation of the lower thrust plate at start-up and touch-down is therefore reduced. The amount of opposing magnetic force is easily controlled by selecting the spacing between the magnets. <IMAGE> |
