Optical Pen Multi-Source Illumination for Uniform Position Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical pens using light-based position detection suffer from non-uniform sensing due to varying light reflection based on the pen's orientation, leading to inconsistent performance across different angles and orientations.
Innovation Solution
The optical pen employs multiple light sources and a power controller to adjust their power levels based on the pen's inclination and rotation angles, ensuring consistent light reflection to the sensor regardless of orientation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single light source is used for position detection, then the device structure is simple, but the sensing uniformity across different orientations deteriorates
Solution Approach 1:
The patent divides the single light source into multiple light sources (first light source, second light source, third light source) positioned at different locations and orientations. Each light source independently illuminates the target from its specific direction, ensuring that at least one light source maintains optimal illumination regardless of the pen's orientation, thereby solving the sensing uniformity problem while maintaining reasonable structural complexity
Solution Approach 2:
Different light sources are assigned different functions based on their positions: the first and second light sources face in a first direction for primary illumination, while the third light source faces in a second direction crossing the first direction for supplementary illumination. This local differentiation ensures comprehensive coverage across all orientations without requiring complex control mechanisms
2Device complexity
If light source power is fixed, then the control system is simple, but the sensing consistency across orientations deteriorates
Solution Approach 1:
The patent implements dynamic power adjustment for the multiple light sources based on the detected orientation of the pen. The controller modifies the emission intensity of each light source according to its position and the current orientation, ensuring that the total illumination remains consistent regardless of which light source is primarily active, thereby achieving sensing consistency through adaptive control
Solution Approach 2:
The system uses a sensor to detect the orientation of the pen and provides feedback to the controller, which then adjusts the power of the light sources accordingly. This closed-loop control ensures that the illumination conditions remain optimal and consistent across different orientations, solving the sensing consistency problem with a manageable control system
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
This design minimizes sensing non-uniformity by uniformly maintaining light reflection to the sensor, enhancing the pen's performance across a range of orientations and angles.
Implementation Method 1
a light sensor configured to receive external light
Data Source
AI summary
An optical pen includes a body, a protrusion connected to the body and protruding in a first direction, a first light source configured to output light in the first direction, a second light source configured to output light in the first direction, a third light source configured to output light in a second direction crossing the first direction, a light sensor configured to receive external light; and a power controller configured to separately control power of the first light source and power of the third light source.