Optical MEMS Transducer Planar Alignment for Signal Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical MEMS microphones face issues with multiple reflections affecting the measured optical signal due to the reflective surfaces of the membrane and backplate being in different planes, leading to inconsistent signal deflection measurements.
Innovation Solution
The reflective elements of the membrane are formed in the same plane as the diffraction grating, reducing multiple reflections and ensuring consistent signal measurement by maintaining the reflective surfaces in the same plane, thus improving the accuracy of pressure signal conversion to electrical signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the reflective surfaces of the membrane and backplate are in different planes, then the device structure is simpler to manufacture, but multiple reflections occur affecting the measured optical signal
Solution Approach 1:
The patent aligns the reflective surfaces of the membrane and backplate in the same plane (z-dimension), eliminating the dimensional offset that causes multiple reflections. This planar alignment resolves the measurement precision issue while maintaining manufacturing simplicity through standard fabrication processes.
2Measurement precision
If the reflective elements are arranged in the same plane, then multiple reflections are reduced improving signal measurement accuracy, but the device complexity increases
Solution Approach 1:
The patent merges the diffraction grating and reflective elements into a single co-planar structure on the backplate. This integration reduces device complexity by eliminating the need for separate out-of-plane components while maintaining the benefit of reduced multiple reflections and improved signal measurement accuracy.
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 configuration enhances the performance of optical MEMS microphones by minimizing signal interference and improving the accuracy of pressure signal conversion, resulting in more reliable transduction of sound waves into electrical signals.
Implementation Method 1
a diffraction structure including alternating first reflective elements and openings arranged in a first plane
Implementation Method 2
a reflection structure including second reflective elements and configured to deflect with respect to the diffraction structure
Data Source
AI summary
According to an embodiment, an optical MEMS transducer includes a diffraction structure including alternating first reflective elements and openings arranged in a first plane, a reflection structure including second reflective elements and configured to deflect with respect to the diffraction structure, and an optical element configured to direct a first optical signal at the diffraction structure and the reflection structure and to receive a second optical signal from the diffraction structure and the reflection structure. The second reflective elements are arranged in the first plane when the reflection structure is at rest. Other embodiments include corresponding systems and apparatus, each configured to perform various embodiment methods.