Image blurring caused by vibrations is a factor whose influence on resolution is often significant in imaging systems that involve mechanical motion. For example, an unstabilized, airborne system mounted on vibration isolators experiences an angular velocity typically on the order of 60,000 μrad/s. On the other hand, a stabilized system, which obtains image motion corrections by moving optical elements so as to counteract sensor motions, has a residual error typically on the order of 2500 μrad/s involving pitch, roll, yaw, and forward motion compensation errors. The greatest errors result usually from rotational vibration. A stabilized mount-type system has a combined error typically on the order of 100 μrad/s [14.1]. Even where no motion is involved, as in large fixed-position astronomical telescopes, vibrations deriving from thermal gradients in the walls and other parts of the telescope can be the limiting factor in image resolution.
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