Optical Fiber Characteristic Measuring Device Polarization Independence
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Brillouin optical correlation domain reflectometry (BOCDR) methods face challenges in reducing measurement time due to polarization dependence and the need for integrating backscattered light, which can lead to longer measurement times and reduced spatial resolution.
Innovation Solution
An optical fiber characteristic measuring device that synthesizes beat components associated with p-polarized and s-polarized light from a continuous wave of light, allowing for polarization-state-independent measurements in a shorter time frame.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a pulse width of an optical pulse is narrowed to improve spatial resolution, then spatial resolution is improved, but signal intensity of backscattered light is reduced and measurement time is increased
Solution Approach 1:
The patent segments the detection process by separating p-polarized and s-polarized light components and processing them independently through different optical paths. This allows simultaneous measurement of both polarization states without requiring time-multiplexed integration, thereby maintaining high spatial resolution while reducing total measurement time.
Solution Approach 2:
The patent employs periodic frequency modulation of the pump light to generate beat components that can be detected through heterodyne detection. This periodic modulation enables the system to extract signal information at specific frequency intervals, allowing for faster acquisition of backscattered light characteristics without requiring long integration times.
2Reliability
If polarization scrambling is performed to eliminate polarization dependence, then measurement stability is improved, but device complexity and measurement time are increased
Solution Approach 1:
Instead of using polarization scrambling to average out polarization effects, the patent segments the detection into two independent channels: one for p-polarized light and one for s-polarized light. By measuring both components separately and combining their results, the system eliminates polarization dependence without requiring scrambling mechanisms, thus reducing device complexity while maintaining measurement stability.
3Reliability
If polarization scrambling is performed to eliminate polarization dependence, then measurement stability is improved, but measurement time is increased
Solution Approach 1:
The patent uses periodic frequency modulation of the pump light to generate detectable beat components through heterodyne detection. This allows the system to rapidly acquire signal information at specific frequency intervals, enabling fast measurement of both p- and s-polarized components simultaneously. The periodic modulation scheme eliminates the need for time-consuming polarization scrambling while maintaining measurement stability through consistent frequency reference.
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 enables faster and more accurate measurements of optical fiber characteristics by eliminating polarization dependence, reducing measurement time, and maintaining high spatial resolution without the need for integrating backscattered light.
Implementation Method 1
Brillouin scattering generated when light is incident on optical fibers, which are one of optical transmission media, is changed in accordance with a strain applied to the optical fibers or a temperature of the optical fibers
Implementation Method 2
The Brillouin scattered light is backscattered light scattered due to an acoustic wave whose speed is changed depending on a strain or a temperature of the optical fiber to be measured
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An optical fiber (F) characteristic measuring device of the present invention includes a light source (10), an optical divider (20), an optical waveguide (30), a first separator (60), a second separator (80), a first interferer (90), a second interferer (100), and a calculator (170). The light source (10) is configured to generate a frequency modulated continuous wave of light. The optical divider (20) is configured to divide the frequency modulated continuous wave of light into first and second divided-waves of light. The optical waveguide (30) is configured to guide the first divided-wave of light to one end of an optical fiber to be measured. The first separator (60) is configured to separate a backscattered light generated by Brillouin scattering of the first divided-wave of light in the optical fiber to be measured into a first scattered light, which is a linearly polarized light, and a second scattered light, which is a linearly polarized light perpendicular to the first scattered light.