Multi-unit Optical System Aberration Control

The optical system is divided into multiple lens units with different refractive powers (positive and negative) that can move independently during focusing. This segmentation allows each lens unit to contribute differently to aberration correction, enabling the system to maintain low aberration fluctuation across a wide imaging magnification range from infinity to close-up shots.

The optical system employs dynamic focusing mechanisms where lens units move along the optical axis during focusing from infinity to close distance. The patent specifies particular movement relationships between lens units (including movement toward image plane and toward object) to dynamically correct aberrations as imaging magnification changes, thereby reducing aberration fluctuation throughout the focusing range.

The focusing system is segmented into multiple independently controllable lens units, each with specific refractive powers. This allows complex aberration correction to be achieved through coordinated movement of simpler individual units rather than requiring a single complex moving assembly, thereby managing device complexity while maintaining high aberration control.

The patent defines specific parameter relationships between lens unit movements (including focal length ratios and movement distance relationships) to optimize aberration correction. By establishing quantitative relationships between movement parameters, the system achieves effective aberration control through coordinated parameter changes rather than requiring complex mechanical structures.