MEMS Piezo Damper for Oscillating Function Element Deformation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
MEMS devices, particularly micromirror devices, face challenges with elastic deformations of the function element at high oscillation frequencies, leading to performance degradation such as planarity loss of the mirror surface and reduced quality of reflected laser beams.
Innovation Solution
The integration of piezo dampers, formed by pairs of piezo elements electrically connected via electronic circuits, at specific locations on the function element to damp alternating elastic deformations by transforming mechanical energy into electrical energy or generating mechanical force against deformations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the structure of the device layer is stiffened to avoid elastic deformations, then the deformation resistance is improved, but the mass of the oscillating parts increases
Solution Approach 1:
The patent replaces the mechanical stiffening approach with an active control system using piezoelectric elements. These elements detect elastic deformations through the piezoelectric effect and generate counteracting forces to compensate for deformations, substituting passive mechanical reinforcement with active electromechanical control. This avoids adding significant mass while maintaining deformation resistance.
Solution Approach 2:
The patent changes the physical state and properties of the function element by integrating piezoelectric elements that can dynamically adjust their mechanical properties. By applying electrical voltages to the piezoelectric elements, the system can alter the effective stiffness and damping characteristics of the oscillating parts, enabling deformation compensation without permanent structural modification or mass addition.
2Object-affected harmful factors
If the moment of inertia of the function element is reduced to minimize elastic deformations, then the deformation influence is reduced, but the structural integrity and stiffness are compromised
Solution Approach 1:
Instead of mechanically reducing the moment of inertia to minimize deformations, the patent uses piezoelectric elements to actively compensate for deformations after they occur. This substitution allows the function element to maintain its optimal structural integrity while the piezoelectric control system counteracts the harmful deformation effects through generated counter-forces.
3Strength
If additional material is applied to stiffen the function element, then the deformation resistance is improved, but the mass of the oscillating parts increases
Solution Approach 1:
The patent substitutes the approach of adding material for stiffening with an active control system using piezoelectric elements. These elements are integrated into the existing structure and provide deformation compensation through electromechanical coupling, avoiding the need to add significant material mass while achieving the desired stiffness enhancement.
Solution Approach 2:
The patent creates a composite structure by integrating piezoelectric elements with the function element. This composite approach combines the structural properties of the base material with the active deformation-compensating properties of the piezoelectric material, achieving enhanced stiffness without proportionally increasing mass, as the piezoelectric elements are typically thin layers.
4Manufacturing precision
If piezo dampers are integrated to damp elastic deformations, then the planarity and quality of reflected beam are improved, but the device complexity increases
Solution Approach 1:
The piezoelectric elements serve multiple functions simultaneously: they act as sensors to detect elastic deformations through the piezoelectric effect, and as actuators to generate counteracting forces to compensate for these deformations. This multi-functionality reduces the need for separate sensing and actuating systems, thereby limiting the increase in device complexity while achieving improved planarity and beam quality.
Solution Approach 2:
The patent merges the sensing and actuating functions into a single integrated system using piezoelectric elements. The piezoelectric elements are directly coupled to the function element, combining the detection of mechanical deformations and the generation of compensating forces into one unified component, which simplifies the overall device architecture compared to separate sensing and actuation systems.
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 solution effectively reduces elastic deformations, maintaining the planarity of the mirror surface and enhancing the quality of reflected images, while also reducing the energy required for oscillation and minimizing additional mass, thus addressing the limitations of existing technologies.
Implementation Method 1
the at least one piezo damper is configured to damp alternating elastic deformations of the function element by transforming the mechanical energy of the alternating elastic deformations to electrical energy
Implementation Method 2
or by generating mechanical force acting against the alternating elastic deformations based on provided electrical energy
Data Source
Figure 1(a)~1(b)
Figure 2~3(b)
Figure 4a(a)~4a(c)
AI summary
The present disclosure relates to a MEMS device 1100 - 1300 and a method for manufacturing the MEMS device 1100 -1300, the MEMS device 1100 -1300 comprises a device layer 3 comprising spring sections 3a and a function element 3b being spring-mounted by the spring sections 3a, wherein the function element 3b is configured to be driven to oscillate along and/or about at least one oscillation axis X, Y, and at least one piezo damper 8 provided at the function element 3b and configured to damp alternating elastic deformations of the function element 3b resulting from the oscillation.