Vehicular Lighting Lens Segmentation for Cut-Off Line Visibility

The incident surface of the lens is divided into multiple regions with different diffusion part arrangements. The upper incident surface has a first arrangement pattern, the intermediate incident surface has a second arrangement pattern, and the lower incident surface has a third arrangement pattern. This segmentation allows different regions to serve different functions: the upper region provides strong diffusion for driver visibility, while the lower region maintains brighter areas for cut-off line visibility and adjustment operability.

Different regions of the incident surface are given different local qualities in terms of light diffusion. The upper incident surface uses a first arrangement pattern with higher diffusion, the intermediate incident surface uses a second arrangement pattern with moderate diffusion, and the lower incident surface uses a third arrangement pattern with lower diffusion. This local quality variation ensures that each region contributes optimally to either driver visibility or cut-off line visibility depending on its position.

The incident surface is segmented into upper, intermediate, and lower regions with progressively less diffusion. This segmentation allows the cut-off line area (primarily formed by light passing through the intermediate and lower surfaces) to maintain sufficient brightness while the upper surface provides the necessary diffusion for overall light distribution uniformity.

The diffusion strength is varied locally across the incident surface. Regions contributing more to the cut-off line formation (lower and intermediate surfaces) have weaker diffusion to maintain brightness, while regions contributing to overall distribution (upper surface) have stronger diffusion for uniformity. This local quality differentiation resolves the contradiction between uniformity and brightness.