Interferometer Mirror Position Sensing with Shared Vibration Source
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing interferometers face challenges in accurately measuring the position of a movable mirror while minimizing size and power consumption, as they require separate signal sources for driving the movable mirror and a light modulator, leading to increased size and power consumption.
Innovation Solution
An interferometer design that integrates a vibrating element as a signal source for both the mirror drive signal and light modulation, using a vibrating element to drive the moving mirror and modulate the laser beam, thereby eliminating the need for separate signal sources and reducing the device's size and power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If separate signal sources are used for driving the movable mirror and for light modulation, then the measurement accuracy of the movable mirror position is improved, but the device size and power consumption increase
Solution Approach 1:
The patent combines the functions of driving the movable mirror and modulating the laser beam into a single signal source. The vibration signal generated by the movable mirror drive unit is reused as the modulation signal for the laser beam, eliminating the need for a separate signal source and thereby reducing device complexity while maintaining measurement accuracy
Solution Approach 2:
The signal source is designed to serve multiple functions: it both drives the movable mirror for position measurement and modulates the laser beam for interferometric detection. This multi-functional approach reduces the number of components needed while achieving the same measurement objectives
2Measurement precision
If separate signal sources are used for driving the movable mirror and for light modulation, then the measurement accuracy of the movable mirror position is improved, but the power consumption increases
Solution Approach 1:
The patent merges the power requirements for mirror driving and light modulation into a single signal source system. By reusing the same vibration signal for both purposes, the system eliminates redundant power consumption associated with operating a separate signal source and its associated electronics
Solution Approach 2:
The system uses the mechanical vibration signal generated by the movable mirror drive unit itself as the modulation signal, rather than requiring an external power source for signal generation. This self-service approach reduces overall power consumption while maintaining measurement capabilities
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 integration allows for accurate measurement of the movable mirror position with reduced size and power consumption, enhancing the interferometer's analytical accuracy and spectral pattern generation.
Implementation Method 1
The measurement light incident from a first light source through a measurement target passes through the light incident unit and is split in the beam splitter unit. A part of the measurement light thus split is reflected by the movable mirror and then returns to the beam splitter unit. The rest of the measurement light thus split is reflected by the fixed mirror and then returns to the beam splitter unit.
Implementation Method 2
A part of the measurement light thus split is reflected by the movable mirror and then returns to the beam splitter unit. The rest of the measurement light thus split is reflected by the fixed mirror and then returns to the beam splitter unit.
Implementation Method 3
The part and the rest of the measurement light having returned to the beam splitter unit are detected by the first photodetector as interfering light.
Implementation Method 4
The part and the rest of the laser beam having returned to the beam splitter unit are detected by the second photodetector as the interfering light.
Implementation Method 5
it is considered to measure the position of the movable mirror using optical heterodyne interferometry
Implementation Method 6
a light modulator configured to modulate a frequency of the laser beam using a vibrating element and add a modulation component
Implementation Method 7
a waveform called an interferogram is obtained by determining an intensity of the measurement light at each position of the movable mirror
Data Source
AI summary
An interferometer including an analysis unit and a length measurement unit, wherein the analysis unit includes an analysis optical system that includes a first light source configured to emit an analysis light, a moving mirror that reflects the analysis light, and a first light receiving element that receives the analysis light, and is used for analysis of the sample using interference of the analysis light, and a mirror drive unit that drives the moving mirror based on a mirror drive signal, the length measurement unit includes a length measurement optical system that includes a laser source, a light modulator that adds a modulation component by modulating a frequency of the laser beam using a vibrating element, and a second light receiving element that receives the laser beam including the length measurement component and the modulation component generated when the moving mirror is irradiated with the laser beam, and outputs a second received light signal, and is used for detection of a position of the moving mirror using interference of the laser beam, and the vibrating element is a signal source of the mirror drive signal.