Injection-Locked Resonator Fiber Gyroscope Without Complex Locking Loops
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fiber optic gyroscopes face challenges with high-power laser usage causing refractive index variations due to the Kerr effect and require complex locking loops, which increase cost and complexity.
Innovation Solution
The implementation of injection locking in fiber optic gyroscopes reduces the need for high-powered lasers and eliminates the requirement for high-quality locking loops by using laser feedback to lock frequencies to resonator resonance peaks, thereby minimizing the Kerr effect and simplifying the system design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high-powered lasers are used in conventional fiber optic gyroscopes, then accurate rotation rate measurements can be achieved, but refractive index variations occur due to the Kerr effect
Solution Approach 1:
The patent changes the operating parameters by using injection-locked lasers that operate at stabilized frequencies matched to resonator modes, rather than high-powered continuous-wave lasers. This parameter change maintains measurement precision while avoiding the Kerr effect-induced refractive index variations that occur with high power levels.
Solution Approach 2:
The patent implements feedback through injection locking where a portion of the resonator output is fed back to the laser source, stabilizing its frequency to match the resonator modes. This feedback mechanism enables accurate rotation measurements while operating at lower power levels that do not trigger significant Kerr effects.
2Measurement precision
If complex locking loops are implemented in conventional fiber optic gyroscopes, then laser frequency can be stabilized to resonator modes, but device complexity and cost increase
Solution Approach 1:
The patent employs self-service through the injection locking mechanism where the resonator itself provides the frequency reference that automatically stabilizes the laser. The system uses the resonator's own modes to lock the laser frequency without requiring external complex control loops, thereby simplifying the device while maintaining frequency stabilization precision.
Solution Approach 2:
The patent merges the laser frequency stabilization function with the resonator structure itself. By combining the injection-locked laser with the resonator in a unified configuration where the resonator provides both the measurement function and the frequency reference, the patent eliminates the need for separate complex locking loops while achieving precise frequency stabilization.
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 reduces the need for high-powered lasers and complex control loops, lowering costs and reducing refractive index variations, while maintaining accurate rotation rate measurements.
Implementation Method 1
The two counter-propagating (e.g., CW and CCW) beams experience different pathlengths while propagating around a rotating closed optical path, and the difference in the two pathlengths is proportional to the rotational rate that is normal to the enclosed area.
Implementation Method 2
at least one return path that injects a first optical feedback, associated with the first laser, and a second optical feedback, associated with the second laser, from the optical resonator into the at least one laser source, wherein the first optical feedback locks the first launch frequency to a first resonance frequency of the optical resonator and the second optical feedback locks the second launch frequency to a second resonance frequency of the optical resonator
Implementation Method 3
Conventional fiber optic gyroscopes face challenges with high-power laser usage causing refractive index variations due to the Kerr effect
Data Source
Figure 1A~1B
Figure 2
Figure 3
AI summary
Systems and methods for an injection locking RFOG are described herein. In certain embodiments, a system includes an optical resonator. The system also includes a laser source configured to launch a first laser for propagating within the optical resonator in a first direction and a second laser for propagating within the optical resonator in a second direction that is opposite to the first direction, wherein the first laser is emitted at a first launch frequency and the second laser is emitted at a second launch frequency. Moreover, the system includes at least one return path that injects a first optical feedback for the first laser and a second optical feedback for the second laser, from the optical resonator, into the laser source, wherein the first and second optical feedbacks respectively lock the first and second launch frequencies to first and second resonance frequencies of the optical resonator.