What is the purpose of high-speed rotation in X-ray tubes?

High-speed rotation in X-ray tubes is primarily aimed at improving anode performance. When rotating at high speeds, the anode can distribute heat more effectively across its surface. This is vital because X-ray production generates significant heat, which can damage the anode if not managed properly. The rotation allows for a larger area to be utilized for X-ray production, which helps in preventing localized overheating. A well-functioning anode with optimal performance ensures higher efficiency in X-ray generation, leading to better image quality and more efficient energy use.

Other options do not capture the essential benefit of high-speed rotation. Increasing image brightness is primarily influenced by the dose of radiation and the sensitivity of the imaging medium rather than the rotation speed itself. Spatial resolution improves based on factors like focal spot size and imaging techniques rather than the anode’s rotation speed. While high-speed rotation does contribute to heat management, it does not inherently reduce heat production; rather, it enhances the anode's ability to handle the heat generated during X-ray exposure.