Healthy Lighting LED System with Spectral Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current light-emitting systems, particularly those using violet LEDs to excite blue, green, and red LEDs, emit harmful wavebands such as near-ultraviolet and high-energy blue light, which can damage human eyes and disrupt circadian rhythms, while lacking optimal color rendering performance.
Innovation Solution
A light-emitting system that emits white light within a 2700 K-6500 K color temperature range, with specific spectral power distributions that minimize harmful wavebands (380 nm-405 nm and 415 nm-455 nm) and maximize beneficial wavebands (465 nm-495 nm), using a combination of phosphors excited by a UV chip, ensuring energy proportions and integral ratios align with solar spectral curves for improved color quality and safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If violet LED is used to excite blue, green, and red phosphors to obtain continuous spectrum, then color rendering performance is improved, but harmful wavebands (near-ultraviolet and high-energy blue light) are emitted causing eye damage
Solution Approach 1:
The patent extracts and removes the harmful near-ultraviolet waveband (380-405 nm) and high-energy blue light waveband (415-455 nm) from the continuous spectrum emitted by conventional violet LED excitation, while preserving the beneficial visible spectrum for color rendering. This is achieved by selectively filtering out the harmful wavebands through optical filters or by redesigning the phosphor composition to not emit in these ranges.
Solution Approach 2:
The patent changes the spectral parameters by adjusting the phosphor materials and their ratios to modify the emission spectrum. Specifically, it optimizes the blue phosphor FWHM (20-100 nm), green phosphor FWHM (20-80 nm), yellow phosphor FWHM (60-120 nm), and red phosphor FWHM (80-120 nm) to achieve a continuous spectrum without harmful wavebands, thereby improving color rendering while eliminating eye-damaging radiation.
2Use of energy by moving object
If conventional white LED structure is used to achieve high luminous efficiency, then energy conversion is improved, but harmful spectral components remain that disrupt circadian rhythms and cause visual fatigue
Solution Approach 1:
The patent converts the potentially harmful high-energy blue light into beneficial long-wave blue light (465-495 nm) by adjusting the phosphor down-conversion process. Instead of simply filtering out all blue light, it transforms the short-wave blue light (415-455 nm) into long-wave blue light through phosphor materials with specific emission characteristics, thereby eliminating the harmful effects while maintaining the circadian rhythm-regulating benefits.
3Illumination intensity
If phosphor combination is optimized for continuous spectrum, then color quality is improved, but harmful wavebands cannot be eliminated
Solution Approach 1:
The patent uses composite phosphor materials with specific compositions and ratios to achieve a continuous spectrum without harmful wavebands. The composite structure includes blue phosphor (aluminate, chlorophosphate, or silicate with FWHM 20-100 nm), green phosphor (oxynitride, silicate, or aluminate with FWHM 20-80 nm), yellow phosphor (aluminate, silicate, or nitride with FWHM 60-120 nm), and red phosphor (nitride, sulfide, or fluoride with FWHM 80-120 nm), excited by a UV chip (380-430 nm). This composite approach allows simultaneous optimization of color quality and elimination of harmful emissions.
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 system reduces harmful spectral outputs and enhances beneficial outputs, achieving healthy lighting by limiting hazardous wavebands and aligning with solar spectral curves, thereby reducing eye damage and optimizing circadian rhythm regulation.
Implementation Method 1
The phosphors are composed of a blue phosphor (having a main emission peak of 430 nm-500 nm), a green phosphor (having a main emission peak of 480 nm-550 nm), a yellow phosphor (having a main emission peak of 540 nm-600 nm), and a red phosphor (having a main emission peak of 600 nm-700 nm), wherein, the blue phosphor is aluminate, chlorophosphate or silicate
Implementation Method 2
a relative spectral power distribution of a solar spectral curve corresponding to the color temperature is set to be S (λ), wherein the solar spectral curve is a black body radiation curve corresponding to the color temperature
Data Source
AI summary
A light-emitting system for healthy lighting, a light bar and a light fixture, wherein they are applied to the field of lighting and can emit white light with a color temperature range of 2700 K to 6500 K. A relative spectral power of the light-emitting system is set to be ϕ (λ), and a relative spectral power distribution of a solar spectral curve corresponding to the color temperature is set to be S (λ). The white light has a first characteristic waveband, and a wavelength region of the first characteristic waveband is 380-405 nm. The white light has a second characteristic waveband, and a wavelength region of the second characteristic waveband is 415-455 nm. The white light has a third characteristic waveband, and a wavelength region of the third characteristic waveband is 465-495 nm.