Fork-Shaped Quartz Tines in Torsional Mode for Low-Noise Temperature Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing quartz crystal devices for temperature sensing lack high sensitivity and linearity in frequency response, and are prone to amplitude noise, limiting their ability to detect fine temperature changes effectively.
Innovation Solution
A fork-shaped quartz crystal device configured to vibrate in a torsional mode, featuring a pair of elongate tines with mesa or groove structures and electrodes that twist about a horizontal axis when a bias is applied, enhancing sensitivity and linearity of frequency response while minimizing amplitude noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional quartz crystal devices are used for temperature sensing, then basic temperature detection is possible, but sensitivity to temperature changes is insufficient and frequency response linearity is poor
Solution Approach 1:
The patent employs torsional mode vibration of the quartz crystal tines to generate frequency responses that are highly sensitive to temperature changes. The mechanical torsional vibration mode produces a more linear frequency-temperature relationship compared to conventional vibration modes, thereby simultaneously improving measurement precision and reliability.
Solution Approach 2:
The patent changes the vibrational mode parameter from conventional modes to torsional mode, which fundamentally alters the frequency response characteristics. This parameter change enables both higher temperature sensing sensitivity and improved frequency response linearity, resolving the technical contradiction.
2Measurement precision
If conventional quartz crystal devices operate at higher amplitudes to improve signal strength, then detection capability increases, but amplitude noise increases significantly
Solution Approach 1:
By utilizing torsional mode vibration instead of conventional vibration modes, the patent achieves a vibration mode that is inherently less susceptible to amplitude noise. The torsional motion generates frequency modulations that are more robust against amplitude variations, allowing for improved detection capability without proportionally increasing amplitude noise.
Solution Approach 2:
The patent replaces the conventional vibration mechanism with a torsional vibration mechanism, which fundamentally changes how the signal is generated. This substitution results in a measurement system where frequency responses are less dependent on vibration amplitude, thereby reducing amplitude noise while maintaining detection capability.
3Speed
If quartz crystal devices are designed for high frequency response to improve temperature detection speed, then response time improves, but power consumption increases
Solution Approach 1:
The torsional mode vibration design enables the quartz crystal to operate at optimized frequencies that provide rapid temperature response. The mechanical characteristics of torsional vibration allow for efficient energy transfer and faster thermal coupling, achieving high detection speed with lower power requirements compared to conventional designs.
Solution Approach 2:
By changing the vibrational mode to torsional mode, the patent optimizes the frequency response characteristics to achieve faster temperature detection. This parameter change enables the device to reach steady-state frequency responses more quickly, improving detection speed while the efficient torsional mechanics reduce the power needed to sustain vibration.
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 device achieves high sensitivity to temperature changes with a linear frequency response, immune to amplitude noise, enabling precise temperature detection and efficient vibration with reduced power consumption.
Implementation Method 1
A quartz crystal oscillator vibrates at a stable frequency by being distorted by an electric field when voltage is applied to an electrode near or on the crystal. This property is known as electrostriction or inverse piezoelectricity.
Implementation Method 2
When the field is removed, the quartz, which oscillates in a precise frequency, generates an electric field as it returns to its previous shape, which in turn can generate a voltage.
Data Source
AI summary
The disclosed technology generally relates to quartz crystal devices and more particularly to quartz crystal devices configured to vibrate in torsional mode. In one aspect, a quartz crystal device configured for temperature sensing comprises a fork-shaped quartz crystal comprising a pair of elongate tines laterally extending from a base region in a horizontal lengthwise direction of the fork-shaped quartz crystal, wherein each of the tines has formed on one or both of opposing sides thereof a pair of vertically recessed groove structures laterally elongated in the horizontal lengthwise direction, wherein the pair of groove structures are separated in a horizontal widthwise direction by a line structure. The quartz crystal device further comprises a first electrode and a second electrode formed on the one or both of the opposing sides of each of the tines and configured such that, when an electrical bias is applied between the first and second electrodes, the fork-shaped quartz crystal vibrates in a torsional mode in which each of the tines twists about a respective axis extending in the horizontal lengthwise direction.