Directional Ambient Light Sensor Angular Discrimination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ambient light sensors in electronic devices often struggle to accurately distinguish between bright outdoor conditions and low-intensity directional indoor lighting, leading to inappropriate adjustments in screen brightness.
Innovation Solution
A directional ambient light sensor is mounted in the electronic device's housing, featuring detectors on a semiconductor substrate with incident light angle restriction structures that allow light from different angles to be measured, enabling the creation of an intensity versus angle of incidence profile, and includes both diffuse and directional light detectors to differentiate between lighting types.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a conventional ambient light sensor is used, then the device can detect ambient light intensity, but the sensor cannot accurately distinguish between bright outdoor conditions and low-intensity directional indoor lighting
Solution Approach 1:
The sensor is divided into multiple detectors (first detector and second detector) with different angular sensitivities. The first detector is sensitive to light from a first angle range while the second detector is sensitive to light from a second angle range, allowing the system to distinguish between different lighting conditions by comparing signals from these segmented detection channels.
Solution Approach 2:
Each detector is assigned a specific angular sensitivity profile tailored to its location and function. The first detector has optimized angular sensitivity for detecting outdoor light conditions, while the second detector has optimized angular sensitivity for detecting indoor directional light, creating local quality differences that enable accurate lighting condition discrimination.
2Measurement precision
If the sensor uses multiple detectors with different angular sensitivities, then lighting condition discrimination improves, but the device complexity increases
Solution Approach 1:
Multiple detectors with different angular sensitivities are integrated into a single sensor package with a unified structure. The detectors are positioned and configured to work together as a coordinated system, merging their individual detection capabilities into a comprehensive lighting condition analysis function while sharing common support structures and signal processing pathways.
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 solution enhances the accuracy of ambient light measurements, allowing for precise adjustments in display brightness and visual effects, improving the device's response to varying lighting conditions.
Implementation Method 1
The directional ambient light sensor may be formed from detectors on a semiconductor substrate. Each opening may be configured to allow light with a different range of angle of incidence values to be passed to a respective one of the detectors.
Data Source
AI summary
An electronic device may be provided with a display mounted in a housing. A directional ambient light sensor may measure the intensity and direction of ambient light. The ambient light sensor may be mounted in alignment with a light sensor window formed in an inactive area of the display. The ambient light sensor may be formed from detectors on a semiconductor substrate. Incident light angle restriction structures may define openings for each detector. Each opening may be configured to allow light with a different range of angle of incidence values to be passed to a respective one of the detectors. The ranges of acceptance angle for adjacent detectors may overlap. A sensor may produce a diffuse light reading by processing ambient light data from a diffuse light detector and a directional light detector. The diffuse and directional light detectors may be formed on a common semiconductor substrate.