Corner Focus Control for Short-Throw Projector Image Quality

The patent divides the focus adjustment into two independent segments: back focus adjustment for the central region and corner focus adjustment for the outer regions. This segmentation allows each region to be optimized independently, resolving the contradiction by enabling precise focus control in both center and corners simultaneously, thereby maintaining ease of operation while achieving large screen display with a short focus projector.

The patent applies local quality by implementing independent focus control mechanisms for different regions of the projection image. The back focus lens group handles central region focus, while the corner focus lens group handles outer region focus. This localized approach ensures that each region receives appropriate focus adjustment tailored to its specific requirements, solving the focus adjustment difficulty in short focus projectors.

The patent segments the optical system into two independent focus adjustment mechanisms: a back focus lens group for central region focus and a corner focus lens group for outer region focus. This segmentation enables simultaneous optimization of focus quality in both regions, resolving the contradiction where large projection angles cause outer region defocusing while maintaining short focal distance.

The patent implements local quality control by providing dedicated corner focus lens groups that specifically address the focus requirements of the outer regions. The corner focus adjustment mechanism independently controls the focal position for corner areas, ensuring high focus quality in outer regions even when using large projection angles with short focal distances.

The patent divides the focus adjustment function into two independent segments: back focus adjustment controlled by a back focus lens group for the central region, and corner focus adjustment controlled by a corner focus lens group for the outer regions. This segmentation resolves the contradiction by enabling simultaneous precise focus control in both central and outer regions, eliminating the trade-off between central and outer region focus quality.

The patent applies local quality by implementing region-specific focus control mechanisms. The back focus lens group optimizes focus for the central region, while the corner focus lens group independently optimizes focus for the outer regions. This localized approach ensures that both central and outer regions achieve high focus quality simultaneously, resolving the manual adjustment limitation.

The patent segments the focus adjustment mechanism into two independent systems: back focus adjustment for central region and corner focus adjustment for outer regions. Each segment can be adjusted independently through simple rotational movements of their respective lens groups. This segmentation maintains device complexity at an acceptable level while enabling automatic or semi-automatic focus adjustment that improves setup efficiency and productivity.

The patent utilizes parameter changes by allowing the back focus and corner focus lens groups to rotate independently, changing the focal position parameters for different regions. This parameter-based control approach simplifies the adjustment process compared to complex mechanical systems, enabling quick setup while maintaining the large projection angle capability for high productivity.