MEMS Speaker with Thermo-Acoustic Woofer and Mechanical Tweeter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing MEMS devices for broadband speaker applications face challenges in integration due to size constraints and require improved efficiency for full audio bandwidth support, particularly in tweeter-woofer-systems where electrodynamic speakers are broadband but space-intensive.
Innovation Solution
A MEMS device comprising a housing with a common back volume for both a woofer and a tweeter speaker arrangement, where the woofer is based on a thermo-acoustic principle and the tweeter on a mechanically actuated membrane structure, both actuated at audio frequencies, with control circuitry for signal processing and ultrasonic demodulation to generate full bandwidth acoustic signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If electrodynamic speakers are used for broadband audio coverage, then sound pressure level and bandwidth are improved, but device volume and integration difficulty increase
Solution Approach 1:
The audio frequency range is segmented into two distinct bands handled by separate speaker arrangements: a first speaker arrangement for lower frequencies and a second speaker arrangement for higher frequencies. This segmentation allows each speaker to be optimized for its specific frequency range, achieving broadband coverage without requiring a single large electrodynamic speaker.
Solution Approach 2:
The patent implements a nested structure where the second speaker arrangement is positioned within or adjacent to the first speaker arrangement, and both share a common back volume housed within a single housing. This nesting approach enables compact integration of multiple speaker functions while maintaining the acoustic performance needed for broadband audio coverage.
2Volume of stationary object
If multiple speaker arrangements are integrated in a compact housing, then device size is reduced, but manufacturing complexity increases
Solution Approach 1:
The housing serves multiple functions simultaneously: it provides the structural enclosure for both speaker arrangements, creates the common back volume shared by both speakers, and provides electrical connection pathways from both speaker arrangements to the external environment. This multi-functionality reduces the need for additional components and simplifies the overall manufacturing process.
Solution Approach 2:
The patent merges several functions into the housing structure: acoustic chamber formation, electrical connectivity provision, and mechanical support for both speaker arrangements. By combining these functions into a single integrated housing rather than separate components, the device becomes more compact and the manufacturing process is simplified despite the presence of multiple speaker arrangements.
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
The solution enables a compact, efficient MEMS device that effectively supports full audio bandwidth with high sound pressure levels, addressing the integration challenges and efficiency needs for broadband speaker applications.
Implementation Method 1
the woofer is based on a thermo-acoustic principle
Implementation Method 2
the tweeter on a mechanically actuated membrane structure
Data Source
AI summary
A MEMS package comprises a first speaker arrangement configured for emitting sound in a first audio frequency range and a second speaker arrangement configured for emitting sound in a different second audio frequency range.