Vehicular Lamp Fitting Separator Design for Low Beam Control

The patent applies local quality by making the entry surface of the projection lens non-spherical specifically in the region where light from the low beam light source enters, while keeping other parts of the lens with standard curvature. This localized modification allows the low beam light distribution pattern to have longer vertical length and lower maximum luminous intensity without affecting the overall optical performance and manufacturing precision requirements.

The patent segments the light paths by using a separator that spatially separates low beam light sources from ADB light sources, and uses different optical path lengths and surface curvatures for each light source type. The low beam light passes through a longer optical path with specific surface curvature to achieve diffusion and naturalness, while ADB light follows a different path that maintains contour clarity, thus resolving the contradiction between the two requirements.

The patent makes the projection lens multi-functional by positioning its focal plane between the upper and lower edges of the separator, allowing a single lens to simultaneously control both low beam light distribution and ADB light distribution. This universal design achieves the desired low beam characteristics (longer vertical length, lower density) without requiring separate optical components, thus reducing overall device complexity despite the sophisticated focal plane positioning.