Textured Micro-Optics for Uniform LED Beam Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LED lighting technologies face challenges in achieving uniform color mixing and smooth beam profiles, particularly in directional applications, where multi-color LEDs often result in patchy light distribution due to the angular distribution of light being close to Lambertian and not well-mixed.
Innovation Solution
Incorporating a textured optical element with a micro-optics array and surface texturing, such as industry-standard surface finishing textures like MT11010 or MT11020, to spread and distribute light, controlling beam width and color mixing by diffusing the light beam and broadening it to a desired angle, while ensuring color spatial uniformity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a reflector or TIR is used to collimate light into a narrow beam angle, then the beam angle is reduced to directional levels, but the light distribution becomes patchy and color mixing is poor
Solution Approach 1:
The optical element is divided into multiple discrete microlenses arranged in an array. Each microlens independently redirects light from the LED, and the collective effect of many small lens elements creates a smooth, uniform beam profile while maintaining directional control. This segmentation allows precise control over light distribution without the patchiness caused by single-element optics.
Solution Approach 2:
Different regions of the optical element have different optical properties - the microlenses are positioned and sized to create specific local light redirection patterns. The texturing is applied selectively to surfaces to control light scattering in particular areas, ensuring uniform color mixing in the beam while maintaining the desired narrow beam angle for directional lighting.
2Illumination intensity
If multi-color LEDs are used to achieve high efficacy white light with high CRI, then color rendering is improved, but uniform color mixing becomes difficult
Solution Approach 1:
The patent uses an array of microlenses that operates in three-dimensional space to mix light from multiple LED chips. By positioning lenses at different heights and orientations, the system creates overlapping light paths that converge to produce uniform color distribution across the beam, transforming the color mixing problem from a two-dimensional surface issue to a three-dimensional volumetric process.
Solution Approach 2:
The microlens array acts as an intermediary optical element between the multi-color LED chips and the target surface. It redirects and overlaps light paths from different color LEDs, ensuring that red, blue-shifted yellow, and other wavelength components are uniformly distributed across the beam profile, achieving smooth color mixing while maintaining high CRI.
3Power
If LED light is emitted with Lambertian angular distribution, then light output is maximized, but beam directionality is lost
Solution Approach 1:
The optical system segments the Lambertian light emission into multiple discrete beams using an array of microlenses. Each microlens captures light from a portion of the LED emission pattern and redirects it at a specific angle, collectively forming a controlled directional beam while utilizing most of the available light output from the LED source.
Solution Approach 2:
The microlens array changes the angular parameter of light emission by redirecting rays at controlled angles. The texturing on lens surfaces further modifies light distribution parameters through scattering effects, transforming the wide Lambertian distribution into a narrow, directional beam profile while preserving overall light output efficiency.
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 achieves a smooth, uniform beam profile and improved color mixing, meeting Energy Star color spatial uniformity specifications by combining micro-optics with surface texturing to broaden the beam angle and enhance light distribution, reducing chromaticity variations within the beam.
Implementation Method 1
an optical feature in the optical element that spreads or distributes light passing through the optical element
Implementation Method 2
providing an optical feature in the optical element that spreads or distributes light passing through the optical element
Implementation Method 3
providing a texturing in at least a portion of the optical feature... to spread and distribute light... by diffusing the light beam
Data Source
AI summary
A method for providing an optical element may include providing an optical feature in the optical element that spreads or distributes light passing through the optical element. The method may also include providing a texturing in at least a portion of the optical feature of the optical element.