Optical Mouse CPI Calibration via Digital Pattern Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional CPI calibration methods for optical mice are either ineffective or require complex equipment, leading to discrepancies between the set and real CPI, resulting in suboptimal user experience due to either insufficient or excessive mouse movement speed.
Innovation Solution
An optical navigation device and method that calibrate CPI by computing the real CPI based on the ratio or difference between the set CPI and the actual motions during a predetermined displacement, using a calibration ruler pattern to determine the relative displacement and adjust the CPI accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional CPI calibration methods are used, then CPI can be set, but the real CPI and set CPI are different due to assembling and manufacturing variations
Solution Approach 1:
The patent implements a feedback mechanism where the optical sensor detects the actual movement distance by counting pixels, compares it with the expected distance based on set CPI, and adjusts the CPI value accordingly. This closed-loop feedback ensures that the real CPI matches the set CPI despite manufacturing variations.
Solution Approach 2:
The optical navigation device performs self-calibration using its own optical sensor and processing circuitry. The device automatically detects its movement relative to the calibration pattern and adjusts its CPI without requiring external calibration equipment, making the system self-sufficient.
2Ease of operation
If CPI is set too low, then the optical mouse can be calibrated simply, but the user feels the optical mouse does not move smoothly
Solution Approach 1:
The patent uses a digital copy of the calibration pattern displayed on a screen as the calibration surface. This allows the optical sensor to detect the pattern without requiring a physical ruler or specialized calibration tool, simplifying the calibration process while maintaining accuracy.
3Speed
If CPI is set too high, then the optical mouse responds quickly, but the user feels the optical mouse moves too fast
Solution Approach 1:
The feedback mechanism measures the actual pixel count during movement and compares it with the expected pixel count. By adjusting CPI based on this comparison, the system ensures that the cursor movement speed matches the user's expectations, preventing both sluggish and excessive movement.
4Ease of operation
If conventional CPI calibration methods are used, then the calibration process is simple, but complicated equipment is required
Solution Approach 1:
The patent replaces physical calibration equipment with a digital calibration pattern displayed on a standard computer screen. The optical sensor captures images of this pattern, and the processing circuitry analyzes the pixel data to determine movement distance, eliminating the need for specialized calibration tools.
Solution Approach 2:
The calibration pattern can be displayed on any standard computer screen, making the calibration process universally applicable without requiring specialized equipment. The same optical sensor used for normal mouse operation is also used for calibration, eliminating the need for separate calibration hardware.
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
Enables simple and effective CPI calibration, ensuring optimal mouse movement speed by accurately adjusting the CPI to match the real motion output, thereby improving user experience.
Implementation Method 1
an optical sensor, configured to sense optical data
Data Source
AI summary
An optical navigation device, comprising: an optical sensor, configured to sense optical data; and a processing circuit, configured to compute motions of the optical navigation device based on the optical data, and configured to output the motions, wherein a first CPI is set to the processing circuit. The processing circuit receives a calibration command to calibrate the first CPI to a second CPI, wherein the second CPI is computed via following steps: (a) computing a real CPI corresponding to times of motions output by the processing circuit during a time interval that a relative displacement between the optical navigation device and a surface reaches a first predetermined distance; (b) computing a ratio between the real CPI and the first CPI or a difference between the real CPI and the first CPI; and (c) generating the second CPI based on the ratio or the difference.