Multi-Emitter Light Source Dimming for Higher Object Chroma
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional light sources experience a muted color perception when dimmed, known as the Hunt Effect, which reduces the vibrancy and saturation of objects being illuminated, making it undesirable for applications where color perception is crucial.
Innovation Solution
A method and device that independently control multiple LED emitters to increase the color gamut while decreasing lumen output, maintaining a constant correlated color temperature, by linearly adjusting the IES TM-30-15 gamut index and chroma shift, thereby counteracting the Hunt Effect.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional light sources are dimmed to reduce lumen output, then energy consumption decreases, but object chroma and color vibrancy deteriorate due to the Hunt Effect
Solution Approach 1:
The light source is divided into multiple LED emitters with different spectral characteristics (e.g., blue LED with cyan phosphor, blue LED with green phosphor, red LED). Each emitter is independently controllable, allowing selective adjustment of their contributions to the overall spectrum. This segmentation enables maintaining spectral power distribution in key regions (cyan, green, red) even when total lumen output is reduced, thereby preserving object chroma during dimming.
2Illumination intensity
If multiple LED emitters are used to maintain color gamut during dimming, then object chroma improves, but device complexity increases
Solution Approach 1:
The multiple LED emitters serve dual functions: they collectively provide the required lumen output and simultaneously shape the spectral power distribution to maintain color gamut. Each emitter type (blue-cyan, blue-green, red) contributes to both overall brightness and specific spectral regions critical for color perception. This multi-functionality reduces the need for additional separate components and simplifies the overall device architecture despite using multiple emitters.
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 enhances object chroma during dimming, maintaining a high color gamut and vibrancy even at lower light levels, improving color perception in applications like residential and hospitality lighting.
Implementation Method 1
A light emitting device includes a plurality of light emitting diodes (LEDs) having different peak wavelengths
Implementation Method 2
The internal controller individually manipulates power to each LED emitter
Data Source
AI summary
A method of increasing the color gamut of a multi-emitter light emitting device when dimming includes the steps of independently driving each emitter in the device, and increasing the lumen output of at least one emitter while simultaneously decreasing the lumen output of at least one other emitter, such that total color gamut increases while total lumen output of the light emitting device decreases. A light emitting device is also disclosed.