Wearable Light Sensing System for Continuous Ambient Monitoring

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Solution Overview

Problem

Existing wearable light sensing devices, such as actigraphy devices, are often covered by clothing, making ambient light measurements unreliable for determining circadian phase and longitudinal light patterns, and smartphones are not always exposed to the environment, leading to inconsistent light level data.

Innovation Solution

A light sensing system that includes primary and secondary light sensors, a central light profile database, and a processor to determine ambient light exposure by using data from sensors worn by the subject, associated devices, and stationary sensors, ensuring continuous and reliable light measurement even when individual sensors are covered.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Duration of action of moving object

If wearable light sensing devices are used for ambient light measurement, then continuous monitoring is achieved, but the measurements become unreliable when covered by clothing

Engineering Contradiction:
Improvecontinuous monitoringVSAvoidmeasurement reliability
Core Design Contradiction:
Duration of action of moving objectVSReliability

Solution Approach 1:

The patent combines multiple light sensing devices worn by the same subject or multiple subjects into a single measurement system. By merging data from multiple sensors, the system achieves both continuous monitoring and reliable measurements, as coverage of one sensor can be compensated by others that remain exposed.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces a server as an intermediary that receives, processes, and validates light measurement data from multiple wearable devices. The server acts as a mediator that can identify and compensate for covered sensors by comparing data across multiple sources, thereby maintaining measurement reliability while enabling continuous monitoring.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If smartphones are used for light level measurement, then convenient data collection is achieved, but the data becomes inconsistent when the device is not exposed to the environment

Engineering Contradiction:
Improvedata collection convenienceVSAvoidlight level accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent implements a feedback mechanism where the system continuously monitors light measurements from smartphones and compares them against expected environmental light levels. When the smartphone is detected to be covered or not exposed to the environment, the system can identify this state and adjust or discard the corresponding measurements, maintaining data accuracy while preserving the convenience of smartphone-based collection.

Inventive Principle:
Principle #23Feedback

3Reliability

If multiple light sensors are deployed to ensure continuous measurement, then measurement reliability improves, but system complexity increases

Engineering Contradiction:
Improvemeasurement reliabilityVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs multiple light sensors that can serve different functions: individual sensors can be used independently for continuous monitoring, while collectively they provide redundant measurements for reliability. The same sensor array can adapt to different measurement scenarios (single subject, multiple subjects, different environmental conditions), reducing the need for specialized equipment and simplifying the overall system architecture.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

The system provides accurate and frequent ambient light exposure data, enabling effective synchronization of the body clock, diagnosis of mood and sleep disorders, and alignment with social schedules, by leveraging data from multiple sources to compensate for occluded sensors.

Implementation Method 1

a sensor unit having at least one light sensor for receiving light and generating an electrical signal in response to an amount of said light

Methodology Applied
Scientific EffectPhotoelectric Effect: Photoelectric Effect

Data Source

PatentEP3126797B1Light information sensing system and method
Publication Date: 2022.05.11 KONINKLIJKE PHILIPS NV
  • EP3126797B1 patent drawingFigure 1
  • EP3126797B1 patent drawingFigure 2
  • EP3126797B1 patent drawingFigure 3

AI summary

The present disclosure pertains to a light sensing system configured to determine an amount of ambient light exposure experienced by a subject. The present invention wirelessly exchanges light information between different wearable devices of the same user and/or between devices of different users. Local and/or central light profile databases are built-up by the system and are shared between the devices so that light data that is typical for a location at a specific time of day and year can be used to estimate current ambient light levels for situations in which no measurement can be taken.