Multilayer Pyroelectric Element with Peripheral Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional multilayer pyroelectric elements face inefficiencies in generating pyroelectric charge due to temperature gradients and reduced thermal conductivity, leading to incomplete utilization of pyroelectric charge, especially when heated or cooled in directions other than the laminating direction.
Innovation Solution
A multilayer pyroelectric element design with specific dimension relationships between faces and extensive external electrode coverage to enhance temperature gradients and internal electrode exposure, ensuring efficient heat transfer and minimizing reverse potential cancellation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional multilayer pyroelectric element is heated or cooled in the laminating direction, then the element structure is simple, but a temperature gradient occurs in the laminating direction causing reverse potential to cancel out the electromotive force, reducing pyroelectric charge utilization
Solution Approach 1:
The element is divided into multiple pyroelectric body layers with internal electrode layers positioned specifically at the outer peripheries. This segmentation allows heat to be applied to multiple surfaces simultaneously, creating temperature gradients that do not cause reverse potential cancellation, thereby resolving the contradiction between structural simplicity and pyroelectric charge utilization.
Solution Approach 2:
The patent transitions from conventional single-direction heating to multi-directional heating by exposing internal electrodes at peripheral surfaces. This dimensional change allows heat application from multiple directions simultaneously, eliminating the temperature gradient issue in the laminating direction while maintaining structural simplicity.
2Adaptability or versatility
If a conventional multilayer pyroelectric element is heated or cooled in a direction crossing at right angles with the laminating direction, then the heating direction is flexible, but the temperature change at positions away from the heated location becomes smaller due to low thermal conductivity and larger element dimension, decreasing pyroelectric charge generation
Solution Approach 1:
By segmenting the element into multiple layers with internal electrodes exposed at peripheral surfaces, the patent enables heat to reach multiple electrode regions simultaneously from different directions. This segmentation overcomes the limitation of low thermal conductivity by reducing the effective heat transfer distance, maintaining pyroelectric charge generation efficiency while preserving heating direction flexibility.
Solution Approach 2:
The patent applies local quality by positioning internal electrodes specifically at the outer peripheries of pyroelectric body layers. This localized electrode placement ensures that regions with better thermal access generate pyroelectric charge more effectively, compensating for the low thermal conductivity of the bulk material while maintaining overall element versatility.
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 design achieves a greater temperature change per unit of time, allowing for increased pyroelectric charge generation and improved sensitivity in power-generating devices and infrared sensors.
Implementation Method 1
Pyroelectricity is a property to generate electric charge as a result of temperature change. Materials that have pyroelectricity (pyroelectric bodies) are utilized in power-generating devices and infrared sensors as pyroelectric elements that utilize electric charges (pyroelectric charges) generated by temperature change
Implementation Method 2
internal electrode layers which are provided between the pyroelectric body layers of the laminate body, and one ends of which extend to the outer peripheries of the adjoining pyroelectric body layers; and external electrodes that connect the alternate internal electrode layers together at the one ends
Implementation Method 3
due partly to low thermal conductivity of the pyroelectric body and partly to a relatively larger dimension of the element in the heating or cooling direction
Data Source
AI summary
A multilayer pyroelectric element includes: a laminate body constituted by multiple pyroelectric body layers laminated in their thickness direction; internal electrode layers which are provided between the pyroelectric body layers, and one ends of which extend to the outer peripheries of the adjoining pyroelectric body layers; and external electrodes that connect the alternate internal electrode layers together at the one ends, wherein “x1>x3 AND x2>x3” are satisfied wherein x1 is a distance between a pair of first faces crossing at right angles with the laminating direction of the pyroelectric body layers, x2 is a distance between a pair of second faces crossing at right angles with the first faces and running parallel with the laminating direction of the pyroelectric body layers, and x3 a is a distance between a pair of third faces crossing at right angles with the first faces and also with the second faces.