Lighting Device Smooth Cut-Off via Light-Modifying Member
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing lighting devices with reflectors often exhibit high light contrast and non-uniform illumination near the light cut-off region, particularly when using multiple point light sources, leading to unpleasant and non-aesthetic lighting effects, especially in Accent Lighting or Spot Lighting applications.
Innovation Solution
A lighting device with a reflective member and a light-modifying member that extends from the reflective member to a second edge, designed to modify light rays passing near the cut-off region, where the second edge modifies more light rays closer to the first edge, smoothing the light cut-off and reducing contrast without disturbing the overall light output.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a reflector with a sharp edge is used to define the light outlet, then the light direction is precisely controlled, but the light contrast becomes too high and the illumination is non-uniform near the cut-off
Solution Approach 1:
The reflector edge is segmented into multiple facets with different orientations. Each facet redirects light rays at slightly different angles, creating a stepped distribution that approximates a smooth cut-off while maintaining precise directional control. This segmentation resolves the contradiction by dividing the sharp edge into multiple controlled segments.
Solution Approach 2:
Different portions of the reflector edge are given different local properties through varying facet angles and orientations. The facets closer to the central axis have different orientations than those at the periphery, allowing each local region to contribute differently to the overall light distribution. This local differentiation enables both precise direction control and improved uniformity.
2Area of stationary object
If multiple punctual light sources are used to illuminate a larger area, then the coverage is increased, but the light cut-off region exhibits non-continuous light sub-regions and high contrast
Solution Approach 1:
Multiple light sources are positioned and oriented to merge their light beams into a unified distribution pattern. The reflector facets are designed to integrate light from different sources, blending the individual beams so that their cut-off regions overlap and create a continuous illumination boundary rather than discrete steps. This merging eliminates the non-continuous sub-regions.
Solution Approach 2:
The solution transitions from considering light sources as separate point entities to treating them as part of a distributed volumetric source. By arranging multiple sources at different positions and orientations, the system creates an extended light-emitting volume that produces a more continuous and uniform cut-off region, adding spatial dimensionality to resolve the continuity issue.
3Illumination intensity
If lenses are added at the reflector outlet to smooth the light beam, then the light uniformity is improved, but the device complexity increases and lighting efficiency may not be optimized
Solution Approach 1:
The light-smoothing function is extracted from a separate lens component and integrated directly into the reflector structure itself. The facets are formed as part of the reflector geometry, eliminating the need for additional optical elements. This extraction reduces device complexity while maintaining the light-uniforming effect.
Solution Approach 2:
The reflector is given multiple functions: it not only redirects light but also performs the light-smoothing function that would otherwise require separate lenses. The same reflective surface that directs light also creates the stepped facet structure that smooths the cut-off region. This multi-functionality reduces component count and simplifies the overall device.
4Illumination intensity
If the light cut-off region is smoothed by modifying more light rays, then the light uniformity is improved, but the light losses increase
Solution Approach 1:
The facets are designed with specific angular parameters that optimize the balance between smoothing and efficiency. By carefully selecting facet angles and orientations, the system redirects light rays to achieve a smooth cut-off while minimizing the number of rays that need to be modified. This parameter optimization ensures that only the necessary portion of light is redirected, reducing overall losses.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively smooths the light cut-off region, reduces light inhomogeneities, and maintains high lighting efficiency by modifying only the light rays in the cut-off area, allowing for easy control of light distribution without altering the reflective member.
Implementation Method 1
a reflector (or reflective member) comprising a reflective surface and a first edge, the first edge forming a light cut-off of light rays passing proximate this first edge... the reflector being arranged to reflect the light emitted by the light source(s)
Implementation Method 2
a light-modifying member adapted to modify lighting feature(s) of light rays... the light-modifying member modifies proportionally more light rays passing proximate the first edge than light rays passing less proximate the first edge
Data Source
AI summary
The invention relates to a lighting device comprising: —at least one light source (11); —a reflective member (20) comprising a reflective surface (22) and an edge (21) (“first edge”) forming a light cut-off of light rays passing in a region adjacent to this first edge (21); —a light-modifying member (30) adapted to modify lighting feature(s) of light rays and having an edge (“second edge”). The light-modifying member (30) extends from the reflective member (20) to this second edge (31) over a surface area defined to receive a part of the light rays passing in said region. The second edge is designed such that, among said part of light rays, the light-modifying member (30) modifies proportionally more light rays passing proximate the first edge than light rays passing less proximate the first edge (21). The invention relates also to said light-modifying member (30) per se.