Reflective Plate Thickness Gradient for Luminance Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing light-emitting devices struggle to achieve uniform luminance distribution and efficient light use while maintaining a compact configuration, leading to in-plane luminance unevenness and reduced luminance contribution.
Innovation Solution
The light-emitting device incorporates a reflective plate with a sloped section thicker than its top surface section, combined with features like high-reflective films, uneven structures, and wavelength conversion sheets, to enhance luminance contribution and uniformity without increasing weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a conventional reflective plate with uniform thickness is used, then the device structure is simple, but the in-plane luminance uniformity deteriorates
Solution Approach 1:
The reflective plate is designed with non-uniform thickness, where the central portion has a first thickness and the peripheral portion has a second thickness different from the first. This local variation in thickness creates different optical path lengths and reflection characteristics in different regions, thereby improving in-plane luminance uniformity across the display surface.
Solution Approach 2:
The invention introduces a thickness dimension variation to the reflective plate structure. By controlling the thickness distribution in the vertical dimension (central vs. peripheral portions), the patent achieves improved luminance uniformity in the horizontal plane, effectively using dimensional transformation to solve the uniformity problem.
2Use of energy by moving object
If the reflective plate thickness is increased to improve light reflection, then the luminance contribution rate improves, but the device weight increases
Solution Approach 1:
Instead of uniformly increasing the reflective plate thickness throughout, the invention applies thickness variation locally - the central portion has one thickness while the peripheral portion has another. This allows optimization of light reflection in the central viewing area without proportionally increasing the overall weight of the entire plate.
Solution Approach 2:
The invention changes the thickness parameter of the reflective plate from a uniform value to a spatially varying value. By adjusting the thickness parameter differently in central and peripheral regions, the patent optimizes the balance between luminance contribution rate and device weight, achieving better light efficiency without linear weight increase.
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
This configuration improves in-plane luminance uniformity and luminance contribution, enabling superior image expression in display apparatuses and uniform illumination in lighting apparatuses.
Implementation Method 1
a backlight is known that uses a resin-made reflective plate that reflects light from a light source
Implementation Method 2
combined with features like high-reflective films, uneven structures, and wavelength conversion sheets
Data Source
Figure 1
Figure 2
Figure 3
AI summary
There is provided a light-emitting device that exhibits superior luminance contribution rate of a light source while reducing in-plane luminance unevenness despite a simple configuration. The light-emitting device includes: a substrate on which one or more light sources are provided; and a reflective plate placed on the substrate. The reflective plate includes: an opening into which the light source is inserted; a sloped section that is sloped relative to the substrate while surrounding the opening, and has a first thickness; and a top surface section that is coupled to a top end of the sloped section, and has a second thickness. The first thickness is greater than the second thickness.