Resonant Pen Position Detection With Adaptive Transfer Frequency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional position detection systems experience attenuation of the pen signal amplitude due to pen pressure, leading to reduced signal-to-noise ratio and decreased accuracy in detection systems, which conventional position detection systems, such as the attenuation of the pen signal amplitude due to pen pressure, resulting in reduced signal-to-noise ratio and detection accuracy.
Innovation Solution
A position detector with a signal processing circuit that includes a transfer coil and electrodes, which generates a transfer signal with a frequency based on detected pen signal information, maintaining resonance energy and amplitude regardless of pen pressure, using a frequency analysis unit to adjust the transfer signal accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single frequency transfer signal is used for position detection, then the system structure is simple, but the pen signal amplitude is attenuated when pen pressure is applied, reducing detection accuracy
Solution Approach 1:
The patent applies the dynamics principle by making the transfer signal frequency variable rather than fixed. The signal processing circuit dynamically adjusts the frequency of the transfer signal based on the detected resonance frequency of the position indicator. This allows the system to maintain resonance conditions even when pen pressure changes cause frequency shifts, thereby preventing signal amplitude attenuation and improving detection accuracy without significantly increasing system complexity
Solution Approach 2:
The patent implements parameter changes by modifying the frequency parameter of the transfer signal. The signal processing circuit detects changes in the resonance frequency of the position indicator and相应地 changes the frequency of the transfer signal to match. This parameter adjustment ensures that the position indicator remains in resonance with the transfer signal, maintaining signal amplitude and detection accuracy under varying pen pressure conditions
2Reliability
If the transfer signal frequency is adjusted to match pen signal resonance frequency, then signal amplitude is maintained, but the system requires frequency analysis and adjustment mechanisms
Solution Approach 1:
The patent applies the feedback principle through a closed-loop frequency adjustment mechanism. The signal processing circuit detects the resonance frequency of the position indicator and uses this information to adjust the transfer signal frequency. This feedback loop ensures that the transfer signal frequency continuously matches the resonance frequency of the position indicator, maintaining signal amplitude stability and reliability while using a relatively simple adjustment mechanism
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 proposed solution suppresses pen signal attenuation, maintaining resonance energy and amplitude, thereby enhancing position detection accuracy and reducing power consumption, even under varying environmental conditions or pen pressure.
Implementation Method 1
a transfer coil that transfers an alternating magnetic field based on a transfer signal to a position indicator
Implementation Method 2
The electric circuit for detecting the pen pressure in the position indicator includes a resonant circuit including a position indication coil and a resonant capacitor
Data Source
AI summary
A position detector includes a plurality of electrodes that, in operation, functions as a sensor and that includes a transfer coil that, in operation, transfers an alternating magnetic field to a position indicator based on a transfer signal; and a signal processing circuit connected to the electrodes. The signal processing circuit, in operation, detects a pen signal generated by the position indicator; obtains, based on the pen signal, first frequency information that includes frequency information of the pen signal; compares the first frequency information and second frequency information that is stored in a memory; generates the transfer signal with a frequency that is based on the frequency information of the pen signal if the first frequency information is determined to have changed based on the second frequency information that is stored in the memory; and transfers the transfer signal to the transfer coil.