Optical Spectrometer Side-Wall Alignment via Interference Fringes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical spectrometers face challenges in accurately determining the absolute orientation and separation of movable side-walls due to indirect measurement methods, which are prone to mechanical changes such as wear and temperature-induced shifts, affecting reproducibility of analysis results.
Innovation Solution
Incorporating an optical position sensor to detect Fabry-Perot interference fringes and generate command signals to align the side-walls to a predetermined orientation, minimizing interference and allowing for direct measurement of absolute separation and angular orientation, thereby compensating for mechanical changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If indirect measurement of side-wall orientation through actuator monitoring is used, then device complexity is reduced, but measurement precision deteriorates due to mechanical wear and temperature changes
Solution Approach 1:
The patent replaces the mechanical measurement system (actuator monitoring) with an optical measurement system. An optical sensor detects the absolute orientation of movable side-walls by measuring the position of interference fringes, thereby eliminating the accumulation of mechanical errors from wear and temperature changes while providing direct, accurate measurement without complex mechanical linkages
Solution Approach 2:
The patent introduces interference fringes as an intermediary to transfer the measurement information. The fringes are formed by optical energy passing through the sample space between side-walls, and their position serves as a mediator that directly indicates the absolute orientation and separation of side-walls, enabling precise measurement without direct mechanical contact or complex actuator monitoring
2Measurement precision
If direct optical measurement of side-wall position is implemented, then measurement precision is improved, but device complexity increases due to additional optical components
Solution Approach 1:
The patent makes the optical detection system multi-functional: the same optical sensor that detects interference fringes for position measurement also detects optical energy for spectrometric analysis. This allows a single optical component to serve dual purposes, reducing overall device complexity while maintaining high measurement precision
Solution Approach 2:
The optical system serves itself by using the same optical path and detector for both measurement functions. The interference fringe detection and spectrometric analysis share common optical components, eliminating the need for separate dedicated measurement equipment and reducing system complexity
3Adaptability or versatility
If movable side-walls are used for sampling space adjustment, then adaptability is improved, but reliability deteriorates due to mechanical wear and orientation changes
Solution Approach 1:
The patent implements a feedback control system where the optical sensor continuously monitors the absolute position and orientation of movable side-walls by detecting interference fringes. This feedback information is used to compensate for mechanical wear and temperature-induced changes, ensuring that the movable side-walls maintain their intended geometry and measurement reproducibility is preserved despite continuous adjustment operations
Solution Approach 2:
The patent replaces mechanical measurement and compensation mechanisms with an optical feedback system. By using optical interference fringe detection to monitor and compensate for mechanical changes in real-time, the system maintains reliability of movable side-walls without relying on mechanical wear-resistant components or complex mechanical compensation devices
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
This approach ensures consistent and reproducible spectrometer measurements by directly monitoring and adjusting the side-wall orientation, reducing the impact of mechanical changes and interference, and providing accurate compositional analysis of samples.
Implementation Method 1
monitor the relative position of the side-walls by means of detecting the intensity of interference fringes which results from incident optical energy having passed through the at least one window after having traversed the distance between the side-walls a plurality of times
Implementation Method 2
measuring wavelength dependent absorption, particularly infra-red absorption, in a sample using typically transmission, reflection or transflectance analysis configurations
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An optical spectrometer (102) comprises an adjustable sampling space (104) having two generally opposing, relatively movable, side-walls (106,108) which are here substantially formed of optically translucent material and between which in use a sample for analysis is charged and an actuator (116) mechanically coupled, here via a worm drive (118), to one or both of the opposing side-walls (108) and operable in response to a command signal applied thereto to effect their relative movement. The spectrometer (102) further comprises an optical position sensor (110,112,114) adapted to detect interference fringes generated by optical energy traversing the distance between the side-walls (106,108) a plurality of times and to generate the command signal in dependence thereof and preferably also adapted to generate an output indexing intensity against an indication of wavelength usable in the spectrometric analysis of a sample material within the sampling space (104).