Multi-Channel Optical Water Testing Device with Reference Detectors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current portable devices for testing water parameters like turbidity, free chlorine, total chlorine, and color lack sensitivity and accuracy, especially in measuring low levels and wide ranges, and do not comply with EPA 180.1 or ISO 7027 standards, with existing devices having stability issues due to unstable LEDs and complex calibration processes.
Innovation Solution
A portable multi-channel device using micro focusing optics, spherical and cylindrical lenses to compensate astigmatism, and orientation rings to stabilize sample vials, along with reference detectors to monitor emitter output variations, enabling accurate measurements of turbidity, color, and chlorine levels compatible with EPA 180.1 and ISO 7027 standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional portable devices are used for measuring water parameters, then the device structure is simple and easy to operate, but the measurement precision and sensitivity are insufficient especially for low levels
Solution Approach 1:
The device is divided into multiple independent optical channels (first optical channel for turbidity, second optical channel for color, third optical channel for chlorine), each with its own light source and detector. This segmentation allows each channel to be optimized for specific measurements while maintaining overall system manageability.
Solution Approach 2:
Reference detectors are introduced as intermediary elements to monitor variations in emitter output. These reference detectors provide feedback signals that compensate for LED instability, thereby improving measurement precision without requiring complete redesign of the optical system.
2Reliability
If conventional devices are used, then the device is portable and easy to use, but the stability is poor due to unstable LEDs and complex calibration processes
Solution Approach 1:
Reference detectors provide continuous feedback on emitter output variations. The system uses this feedback to automatically compensate for LED instability, significantly improving reliability without adding complex manual calibration steps for the user.
Solution Approach 2:
The device performs self-calibration using the reference detectors and compensation algorithms. This eliminates the need for users to perform complex manual calibration procedures, maintaining ease of operation while dramatically improving stability.
3Measurement precision
If conventional devices are used, then the device structure is simple, but the sensitivity to measure low levels and large range to measure high levels is insufficient
Solution Approach 1:
The optical system is segmented into multiple channels with different light sources (UV LED for color, visible LED for chlorine, infrared LED for turbidity) and detectors optimized for specific wavelength ranges. This enables high sensitivity across different measurement ranges without requiring a single complex detector.
Solution Approach 2:
Different optical parameters (wavelengths) are used for different measurements: UV range for color, visible range for chlorine, and infrared range for turbidity. This parameter differentiation allows each channel to operate at peak sensitivity for its specific measurement type.
4Measurement precision
If conventional devices are used, then the device is simple and portable, but it does not comply with EPA 180.1 or ISO 7027 standards
Solution Approach 1:
The device implements separate optical channels that each comply with specific standard requirements: the turbidity channel follows ISO 7027 with infrared LED and 90-degree detection geometry, while the color and chlorine channels follow EPA 180.1 specifications. This segmentation enables standard compliance without requiring a single overly complex system.
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 device provides high sensitivity and accuracy, capable of measuring low levels and wide ranges, improving stability 20-50 times better than prior art, and is compliant with relevant standards, making it suitable for both low-level drinking water and high-load field applications.
Implementation Method 1
a first UV light emitting diode (LED) for emitting UV light, a first main detector to measure intensity of the UV light transmitted via the liquid sample
Implementation Method 2
a second visible light emitting diode for emitting visible light, a second main detector to measure intensity of the visible light transmitted via the liquid sample
Implementation Method 3
a second infrared LED for emitting infrared light, a first detector to measure intensity of infrared light scattered at 90 degrees to a path of the infrared light
Data Source
AI summary
A portable multi-channel device for optically testing of a liquid sample includes a controller; and a sample holder with a cylindrical sample compartment and at least two optical channels respectively for measuring turbidity of the sample liquid and for measuring one other optical property of the sample liquid. Each of the optical channels including: a light source placed at one end of the channel, a main detector placed across the sample compartment from the light source, a reference detector for measuring an intensity of light emitted by the light source, and an excitation focusing optic for directing a light emitted by the light source through the sample compartment towards the main detector. Signals from the reference detector of the channel, the main detector of the channel, and another main detector of another channel perpendicular to the channel are processed by the controller to evaluate the turbidity of the liquid sample.