Tapered Light Guide for Uniform LED Ring Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Smart-home devices face challenges in generating uniform light rings using discrete LEDs, as they often result in non-uniform light output due to high luminous intensity and space constraints, requiring innovative designs to distribute light evenly across a circular output surface.
Innovation Solution
A light ring assembly utilizing a tapered light guide with cutouts for LEDs and transmissive sections that taper in thickness, combined with micro-lenses and reflective masks, to channel and diffuse light uniformly across a circular output surface, ensuring even illumination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If discrete LEDs are used to illuminate smart-home devices, then the device can provide illumination in dark environments, but the light output becomes non-uniform due to high luminous intensity and space constraints
Solution Approach 1:
A light guide is introduced as an intermediary component between the discrete LEDs and the output surface. The light guide includes transmissive sections with varying thickness that channel and diffuse light from the LEDs, transforming the non-uniform high-intensity LED output into a uniform light ring at the output surface.
Solution Approach 2:
The light guide features local variations in thickness across different regions. The transmissive sections have greater thickness near the LEDs to capture and channel their high luminous intensity, and taper to lesser thickness toward the output surface to diffuse the light and achieve uniform distribution across the circular output surface.
2Illumination intensity
If multiple LEDs are used to achieve uniform light distribution, then the light output becomes more even, but the component count and device complexity increase
Solution Approach 1:
The light guide serves as a light-redistributing intermediary that takes input from a minimal number of discrete LEDs and transforms it into a uniform light ring. This eliminates the need to use multiple LEDs arranged in a circular pattern, as the light guide performs the redistribution function that would otherwise require multiple light sources.
Solution Approach 2:
The light guide combines the light output from multiple discrete LEDs into a single uniform light ring at the output surface. By merging the light paths and intensities through the tapered transmissive sections, the system achieves uniform illumination while using fewer LEDs than would be required without the light guide.
3Illumination intensity
If a tapered light guide with varying thickness is used to diffuse light uniformly, then the light output becomes even, but the manufacturing precision requirements increase
Solution Approach 1:
The light guide utilizes controlled changes in the thickness parameter across its structure. The transmissive sections are designed with a specific thickness gradient that transforms the light distribution. This parameter change approach allows the system to achieve uniform light output while the thickness variations can be manufactured using standard molding techniques with appropriate tolerances.
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 generates a uniform and efficient light ring from a minimal number of LEDs, providing consistent illumination in smart-home devices, such as cameras and keypads, while minimizing power consumption and component count.
Implementation Method 1
A light ring assembly utilizing a tapered light guide with cutouts for LEDs and transmissive sections that taper in thickness, combined with micro-lenses and reflective masks, to channel and diffuse light uniformly across a circular output surface
Implementation Method 2
combined with micro-lenses and reflective masks, to channel and diffuse light uniformly across a circular output surface
Implementation Method 3
combined with micro-lenses and reflective masks, to channel and diffuse light uniformly across a circular output surface
Data Source
AI summary
A light ring assembly for a smart-home device may include a plurality of light-emitting diodes (LEDs) and a light guide, where the light guide may include a plurality of cutouts that receive the plurality of LEDs, and a plurality of transmissive sections between the plurality of cutouts where a thickness of the transmissive sections tapers as the transmissive sections extend away from the plurality of cutouts. The light ring assembly may also include an output surface that receives light emitted from the plurality of LEDs through the plurality of transmissive sections, where the output surface is substantially circular.