Solid State Lighting Device Using Segmented Wavelength Emission
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Solution Overview
Problem
Conventional lighting technologies, such as incandescent and fluorescent lights, are inefficient and lack good color rendering index (CRI), making them unsuitable for applications requiring accurate color representation, while solid state light emitters like LEDs struggle to provide white light with high efficiency and long lifespan.
Innovation Solution
A lighting device comprising a combination of solid state light emitters emitting light in specific wavelength ranges (430-480 nm, 555-585 nm, and 600-630 nm) and lumiphors, which together produce a mixture of light with high CRI and efficacy, achieving color coordinates within ten MacAdam ellipses of the blackbody locus on the CIE Chromaticity Diagram.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If incandescent light bulbs are used, then they provide good color rendering (CRI about 95), but they are very energy-inefficient (90% of electricity released as heat)
Solution Approach 1:
The patent segments the white light generation into multiple wavelength components (blue 430-480nm, green 555-585nm, red 600-630nm) using separate solid state light emitters. This segmentation allows each emitter to operate at its peak efficiency while the combined output achieves high CRI, resolving the contradiction between energy efficiency and color rendering.
Solution Approach 2:
The patent uses a composite approach by combining multiple solid state light emitters with different emission spectra (blue LED, green phosphor, red LED) to create a unified lighting system. This composite structure achieves both high energy efficiency (solid state technology) and high CRI (full spectrum coverage) simultaneously.
2Use of energy by moving object
If fluorescent light bulbs are used, then they are more efficient than incandescent (4x improvement), but they still lack good color rendering (CRI 70-85)
Solution Approach 1:
The patent applies local quality by using different types of solid state light emitters for different wavelength regions: blue LEDs for 430-480nm, green phosphors for 555-585nm, and red LEDs for 600-630nm. Each component is optimized for its specific wavelength range, achieving overall high CRI while maintaining energy efficiency.
Solution Approach 2:
The patent combines multiple solid state light emitters with complementary emission spectra to create a composite lighting system. This composite approach ensures full spectral coverage for high CRI while utilizing the energy efficiency of solid state technology, surpassing fluorescent performance.
3Use of energy by moving object
If solid state light emitters (LEDs) are used to achieve high energy efficiency, then they provide long lifespan, but they struggle to produce white light with both high efficiency and high CRI
Solution Approach 1:
The patent segments the white light generation into multiple wavelength components using separate solid state light emitters (blue LED, green phosphor, red LED) rather than relying on a single emitter. This segmentation enables each component to operate at peak efficiency while collectively achieving high CRI, resolving the contradiction between efficiency and color rendering.
Solution Approach 2:
The patent uses a composite structure combining multiple solid state light emitters with different emission spectra to produce white light. This composite approach maintains the energy efficiency and longevity of solid state technology while achieving high CRI through spectral diversity, overcoming the limitations of single-emitter LED designs.
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 provides a high CRI of at least 80 and efficacy of 25 lumens per watt, ensuring accurate color representation and energy efficiency, suitable for various applications.
Implementation Method 1
A lighting device and lighting method include illuminating a first group of solid state light emitters, each emitting light having a dominant wavelength in a range of from about 430 nm to about 480 nm; illuminating a second group of solid state light emitters, each emitting light having a dominant wavelength in a range of from about 600 nm to about 630 nm
Implementation Method 2
exciting a first group of lumiphors, each emitting light having a dominant wavelength in a range of from about 555 nm to about 585 nm
Data Source
AI summary
A lighting device comprising first and second groups of solid state light emitters, which emit light having dominant wavelength in ranges of from 430 nm to 480 nm and from 600 nm to 630 nm, respectively, and a first group of lumiphors which emit light having dominant wavelength in the range of from 555 nm to 585 nm. If current is supplied to a power line, a combination of (1) light exiting the lighting device which was emitted by the first group of emitters, and (2) light exiting the lighting device which was emitted by the first group of lumiphors would, in an absence of any additional light, produce a sub-mixture of light having x, y color coordinates within an area on a 1931 CIE Chromaticity Diagram defined by points having coordinates (0.32, 0.40), (0.36, 0.48), (0.43, 0.45), (0.42, 0.42), (0.36, 0.38). Also provided is a method of lighting.