Optical Mouse Lift Detection via Image Sensor Brightness Analysis

Solution Overview

Problem

Current optical mouse designs face issues with lift detection, leading to false motion detection and unnecessary power consumption due to the addition of extra optical sensing modules, which increase manufacturing costs and reduce the mouse's lifespan.

Innovation Solution

A lift detection method using an optical mouse with an image sensor having multiple sensing units, where average brightness values from consecutive scans are compared to determine if the mouse is lifted, generating signals to indicate the lift state and restore normal operation without adding hardware, thus avoiding false determinations and maintaining low costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If an additional optical sensing module is added to detect lift state, then lift detection accuracy is improved, but manufacturing cost increases and device lifetime decreases

Engineering Contradiction:

Improvelift detection accuracyVSAvoidmanufacturing cost

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent makes the existing image sensor perform dual functions: both capturing images for motion detection and detecting brightness changes for lift state detection. By utilizing the image sensor's capability to capture brightness information, the system eliminates the need for separate optical sensing modules while maintaining accurate lift detection functionality.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines the lift detection function with the existing image processing system by analyzing brightness changes in captured images. Instead of adding a separate detection system, the invention merges lift detection into the image processing workflow, where the same image sensor and processing units handle both motion detection and lift state determination.

Inventive Principle:

Principle #5Merging (Combining)

2Measurement precision

If an additional optical sensing module is added to detect lift state, then lift detection accuracy is improved, but device lifetime decreases

Engineering Contradiction:

Improvelift detection accuracyVSAvoidmouse lifetime

Core Design Contradiction:

Measurement precisionVSDuration of action of stationary object

Solution Approach 1:

The patent makes the existing image sensor perform dual functions: both capturing images for motion detection and detecting brightness changes for lift state detection. By utilizing the image sensor's capability to capture brightness information, the system eliminates the need for separate optical sensing modules while maintaining accurate lift detection functionality.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If additional optical sensing modules are added for lift detection, then lift detection capability is improved, but manufacturing cost increases

Engineering Contradiction:

Improvelift detection capabilityVSAvoidmanufacturing cost

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent makes the existing image sensor perform dual functions: both capturing images for motion detection and detecting brightness changes for lift state detection. By utilizing the image sensor's capability to capture brightness information, the system eliminates the need for separate optical sensing modules while maintaining accurate lift detection functionality.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines the lift detection function with the existing image processing system by analyzing brightness changes in captured images. Instead of adding a separate detection system, the invention merges lift detection into the image processing workflow, where the same image sensor and processing units handle both motion detection and lift state determination.

Inventive Principle:

Principle #5Merging (Combining)

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 method effectively determines the lift state of the optical mouse without increasing hardware costs, preventing false motion detection and conserving power by selectively outputting signals based on brightness changes, thereby enhancing the mouse's functionality and longevity.

Implementation Method 1

the image sensor uses light rays generated by the optical source to continuously scan and capture a plurality of images corresponding to an optical field of the sensing surface

Methodology Applied

Scientific EffectLight: Light

Implementation Method 2

an optical source, for example, a light emitting diode (LED), formed at the bottom side of the mouse emits light on the desktop, and a 2D image sensor is used to capture a special pattern formed by the micro texture of the desktop irradiated by the optical source

Methodology Applied

Scientific EffectPhotoelectric Effect: Photoelectric Effect

Data Source

PatentUS9146627B2Lift detection method for optical mouse and optical mouse with lift detection function

Publication Date: 2015.09.29 PIXART IMAGING INC

AI summary

A lift detection method for an optical mouse and an optical mouse with a lift detection function are presented. An average brightness value of pixels captured by part of sensing units of an image sensor is computed after each scanning, and two average brightness values obtained from two adjacent times of scanning are compared, to determine a brightness change of the pixels in each scanning, thereby acquiring a placing state of the optical mouse accordingly.