Violet Light Illumination for Continuous Occupied-Area Disinfection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Healthcare-associated infections (HAIs) are prevalent due to high microbial loads in healthcare settings, and existing disinfection methods like UVGI are not effective in continuously disinfecting occupied areas, while continuous lighting with non-hazardous disinfecting light is needed to maintain low microbial levels without compromising safety or illumination quality.
Innovation Solution
A lighting system using a 395 nm LED pump light source combined with wavelength-converting materials to produce a high proportion of disinfecting light below 400 nm, maintaining a CRI of at least 80, ensuring continuous disinfection without perceptible shift from the Planckian locus, and meeting safety standards for human exposure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If UV-C radiation is used for disinfection, then microbial load is reduced effectively, but the system cannot operate in occupied areas due to safety hazards
Solution Approach 1:
The patent changes the wavelength parameter of the disinfecting light from traditional UV-C (200-280 nm) to violet light (380-420 nm), specifically using a 395 nm LED. This parameter change allows the system to maintain disinfection effectiveness while eliminating the safety hazards associated with UV-C radiation, enabling operation in occupied areas.
Solution Approach 2:
The patent uses LED technology, specifically 395 nm violet LEDs, which have a longer operational lifespan and lower cost compared to traditional UV-C lamps. The LED-based system provides continuous disinfection without the safety concerns of UV-C, making it suitable for prolonged use in occupied spaces.
2Reliability
If higher concentration of disinfecting light is used, then disinfection effectiveness increases, but the light quality shifts away from the Planckian locus
Solution Approach 1:
The patent uses violet light at 395 nm, which is at the boundary of human perception. By operating at this specific wavelength, the system can deliver high concentrations of disinfecting radiation while minimizing the perceptible impact on light quality. The human eye is less sensitive to this wavelength, allowing higher doses without noticeable color shifts.
Solution Approach 2:
The patent employs excessive action by using violet light concentrations greater than 40% of the overall spectral power distribution, which is higher than traditional lighting systems. Despite this high concentration of disinfecting radiation, the light maintains good color rendering (CRI > 80) because the 395 nm wavelength is near the limit of human visual perception.
3Reliability
If continuous disinfection is implemented, then microbial load is maintained at low levels, but the system complexity increases compared to periodic UV treatment
Solution Approach 1:
The patent combines illumination and disinfection functions into a single lighting system. The 395 nm violet LED-based lights serve dual purposes: providing general illumination for occupied spaces and delivering continuous disinfection. This multi-functionality eliminates the need for separate UV disinfection systems and occupancy sensors, reducing overall system complexity.
Solution Approach 2:
The patent implements continuous disinfection by using LED lighting that operates throughout occupied hours. Unlike periodic UV-C treatment that requires unoccupied spaces, the violet light system provides uninterrupted microbial debulking as long as the area is occupied, maintaining low microbial loads without additional system complexity.
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 effectively reduces microbial loads, including COVID-19, Staphylococcus aureus, and clostridioides difficile, by delivering up to 250% germicidal radiation while maintaining high illumination quality, reducing HAIs and antibiotic resistance, and improving patient outcomes.
Implementation Method 1
at least one pump light emitting diode (LED) for emitting pump light having a peak wavelength of about 395 nm
Implementation Method 2
one or more wavelength converting materials for converting a portion of the pump light to converted light
Data Source
AI summary
A light source for emitting emitted light to reduce microbial load, said light source, comprising: (a) at least one first light source for emitting first light having a peak wavelength less than 400 nm; and (b) at least one second light source for emitting a second light; wherein said emitted light comprises a combination of said first light and said second light, wherein said emitted light has a spectral power distribution (SPD), wherein said SPD has a first power in said SPD between 350 nm and 800 nm, and a second power in said SPD between 350 nm and 420, wherein said second power is at least 40% of said first power, and wherein said emitted light has a CRI of at least 80.