Optical Touchpad Power Saving via Proximity Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Portable electronic devices face limited power-saving benefits due to high power consumption in backlight modules, especially when additional circuitry is required to detect environmental light, which does not effectively extend standby time.
Innovation Solution
An optical touchpad with a light source, specific-light sensing array, proximity detector, and motion detector is used to emit and sense specific light, determining the distance and motion of an object, allowing for selective activation and deactivation of environmental light and motion detection to conserve power, and controlling the backlight module based on user interaction and ambient light.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If additional circuitry is added to detect environmental light intensity, then the backlight module can adjust its intensity based on ambient light, but the power consumption increases due to the extra circuitry
Solution Approach 1:
The patent combines the environmental light detection function with the existing optical touchpad structure by using the same light source and sensing array. The sensing array serves dual purposes: detecting touch inputs and detecting ambient light intensity, eliminating the need for separate detection circuitry and reducing overall power consumption while maintaining backlight adjustment capability
Solution Approach 2:
The optical sensing array is designed to perform multiple functions: it detects both touchpad inputs and environmental light intensity. This multi-functionality allows the system to adjust backlight intensity based on ambient light without requiring dedicated environmental light sensors, thereby reducing power consumption while maintaining the illumination adjustment feature
2Illumination intensity
If the backlight module remains on to provide continuous illumination, then visibility is maintained, but power consumption increases
Solution Approach 1:
The backlight module dynamically adjusts its intensity level based on real-time detection of ambient light conditions. When ambient light is detected to be sufficient, the backlight intensity is reduced or turned off; when ambient light is insufficient, the backlight intensity is increased. This dynamic adjustment maintains visibility when needed while minimizing power consumption during periods when illumination is not required
Solution Approach 2:
The system changes the operational parameter (backlight intensity) based on detected environmental conditions. By monitoring ambient light intensity and adjusting the backlight parameter accordingly, the system optimizes the balance between maintaining visibility and reducing power consumption, allowing the backlight to be dimmed or turned off when ambient light is sufficient
3Ease of operation
If the motion detector remains active to detect user interaction, then touchpad functionality is maintained, but power consumption increases
Solution Approach 1:
The motion detector operates periodically rather than continuously. It activates to detect user interaction only when the optical touchpad is within a predetermined distance of the user's finger, and deactivates when the distance exceeds this threshold. This periodic operation maintains touchpad functionality during relevant periods while significantly reducing power consumption during periods when no interaction is detected
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 approach effectively reduces power consumption by selectively turning off unnecessary components, such as the motion detector and backlight, based on user proximity and ambient light conditions, thereby extending the standby time of portable electronic devices.
Implementation Method 1
The specific-light sensing array is for sensing reflected light of the specific-light reflected by an instruction object
Data Source
AI summary
Optical touchpad includes a light source for emitting light of a specific wavelength, a specific-light sensing array for sensing the specific light after being reflected by an instruction object for accordingly generating a specific-light sensing image, a proximity detector for determining an instruction distance between the instruction object and the optical touchpad according to the specific-light sensing image, and a motion detector for determining path of the instruction object and then outputting a motion signal according to the specific-light sensing image. When the instruction distance is greater than a predetermined value, the motion detector is turned off.