Hafnium Oxide Far-UV Filter for Human-Safe Excimer Sterilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current UV-C sterilization systems are not safe for use in the presence of people and living tissues, as they can emit harmful wavelengths that pose risks to maintenance workers and others, and existing technologies are inefficient and costly.
Innovation Solution
A human-safe UV-C sterilizing bulb with a pass filter constructed of hafnium oxide layers, integrated with an excimer bulb assembly that emits minimal radiation beyond 231 nm, combined with a smart chip for monitoring and reporting conditions, and a design that includes a quartz envelope and external electrodes to prevent contamination and ozone production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If UV-C sterilization systems use shorter wavelengths to kill pathogens more effectively, then pathogen killing efficiency is improved, but safety for human tissue deteriorates
Solution Approach 1:
The UV-C spectrum (100-280 nm) is segmented into different wavelength ranges with distinct functions: 207-222 nm for pathogen destruction and 230-280 nm blocked for safety. The filter divides the spectrum to allow only the beneficial shorter wavelengths while blocking harmful longer wavelengths, resolving the contradiction between effectiveness and safety.
Solution Approach 2:
The patent changes the wavelength parameter by using specific UV-C sources that emit only at 207 nm or 222 nm, combined with a filter that transmits these wavelengths while blocking 230 nm and above. This parameter selection achieves both high pathogen killing efficiency and human tissue safety.
2Productivity
If excimer bulbs emit broader spectrum to increase output, then sterilization coverage is improved, but harmful radiation increases
Solution Approach 1:
The filter extracts and removes the harmful portion of the excimer bulb spectrum (wavelengths 230 nm and above), allowing only the beneficial 207-222 nm range to pass. This extraction enables safe operation while maintaining sterilization effectiveness.
Solution Approach 2:
The filter acts as an intermediary between the excimer bulb and the environment, selectively transmitting useful radiation while blocking harmful radiation. This mediator enables the system to achieve both broad sterilization coverage and safety.
3Ease of operation
If maintenance workers can replace bulbs easily, then ease of operation is improved, but exposure to harmful light increases
Solution Approach 1:
The filter is integrated directly onto the bulb assembly before use, providing built-in protection that cushions maintenance workers from exposure during bulb replacement. This prior protection enables easy maintenance without increasing exposure risk.
Solution Approach 2:
The filter and bulb are merged into a single integrated assembly, ensuring that protection travels with the light source. This combination allows workers to handle and replace bulbs safely without additional protective measures.
4Object-affected harmful factors
If filters block all wavelengths above 230 nm to ensure safety, then human safety is improved, but energy transmission efficiency deteriorates
Solution Approach 1:
The filter exhibits local quality by being highly selective: it completely blocks 230 nm and above for safety, while fully transmitting 207-222 nm for efficiency. This localized wavelength-specific transmission minimizes energy loss while ensuring safety.
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 safe, efficient, and affordable UV-C sterilization system that effectively kills pathogens without harming humans, with enhanced energy transmission and reduced layer requirements, ensuring user safety during maintenance and operation.
Implementation Method 1
a pass filter constructed of a plurality of layers of hafnium oxide... such that the excimer bulb assembly does not emit substantial UV radiation in wavelengths longer than 231 nm
Implementation Method 2
excimer bulb assembly that emits minimal radiation beyond 231 nm
Implementation Method 3
a quartz envelope and external electrodes to prevent contamination
Data Source
AI summary
An excimer bulb assembly including an excimer bulb and a pass filter such that the excimer bulb assembly does not emit substantial UV radiation in wavelengths longer than 231 nm, 232 nm, 233 nm, 234 nm or 235 nm. The wavelengths are measured at an incident angle of zero (0) degrees to the filter plane. The pass filter is preferably constructed of a plurality of layers of hafnium oxide, and most preferably constructed of less than seventy five (75) layers of hafnium oxide. The excimer bulb, pass filter, and two electrical connectors may be adapted to form a cartridge which may be adapted to swivel along its main axis. The cartridge may further include a smart chip. The smart chip may retain and store information regarding the assembly and preferably retains hours of use of the excimer bulb.