Interdigitated Microsensor Layout for Uniform Pressure Sensitivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing microsensors for measuring force or pressure on touch surfaces, such as smartphone screens, suffer from reduced sensitivity due to series connection and are less reliable due to varying support zones and sensitivity to stress orientation.
Innovation Solution
A microsensor design featuring interdigitated electrodes with parallel tracks extending from a strip, offset in mirror symmetry, and incorporating assemblies of nanoparticles between each pair of tracks, allowing for adaptable contour coverage and uniform sensitivity in all directions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If two sensors are mounted in series around a light well, then the sensor can cover a larger surface area, but the sensitivity is reduced due to series connection
Solution Approach 1:
The patent merges multiple sensor functions into a single sensor by implementing multiple interdigitated electrode pairs within one sensor structure. This allows the sensor to cover a larger surface area around the light well while maintaining high sensitivity, as all electrode pairs are connected in parallel rather than in series, thus combining the benefits of large coverage area with high measurement precision.
2Ease of manufacture
If comb-shaped electrodes with rectilinear tracks are used, then the sensor structure is simple to manufacture, but the sensitivity varies depending on touch location and stress orientation
Solution Approach 1:
The patent replaces rectilinear tracks with curved or circular interdigitated electrode tracks. This curvature allows the sensor to respond uniformly to touches applied at different locations and orientations around the light well, maintaining sensitivity uniformity while remaining compatible with standard manufacturing processes like soft lithography.
3Quantity of substance
If the sensor uses interdigitated comb electrodes, then the electrical resistance is reduced compared to two-end electrodes, but the sensor remains sensitive to stress orientation
Solution Approach 1:
The patent employs multiple interdigitated electrode pairs with asymmetric arrangements around the light well. This asymmetric multi-pair configuration ensures that regardless of the stress orientation or touch location, at least one electrode pair will be optimally oriented to detect the force, thus maintaining low electrical resistance while improving response consistency and reliability.
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 microsensor achieves high sensitivity and reliability by reducing electrical resistance and maintaining uniform sensitivity across different touch locations, including those associated with light wells.
Implementation Method 1
Assemblies of conductive or semiconducting nanoparticles in an insulating ligand are intercalated between each pair of tracks
Implementation Method 2
capable of measuring a pressure applied to said surface
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a microsensor (210) comprising a first electrode (211) and a second electrode (212), each electrode comprising a plurality of parallel traces (222), each trace comprising one connected end and one free end, each trace extending from a connector strip (223), said connector strip connecting the traces by the connected ends thereof, the traces of the two electrodes being offset and mirror-symmetrical such that said traces of the two electrodes are interdigitated and comprise, between each pair of interdigitated traces, an assembly of nanoparticles in a ligand, characterised in that each trace (222) comprises at least one change of direction as it extends away from the connector strip (223).