Display Luminance Control for Accurate Ambient Light Detection

Solution Overview

Problem

Conventional light intensity detection methods in electronic devices, such as smartwatches, face reliability issues due to increased contribution of display light to ambient light detection, especially when display luminance is high and external light is low, leading to inaccurate control of display brightness.

Innovation Solution

An electronic apparatus with a light sensor and a control unit that adjusts the display's luminance to a lower threshold when ambient light intensity is low, reducing the display's contribution to the detection value and enhancing the reliability of light intensity detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the luminous intensity of the display is increased to improve visibility, then the display brightness is improved, but the contribution of display light to the light sensor detection value increases, reducing the reliability of ambient light detection

Engineering Contradiction:

Improveluminous intensity of displayVSAvoidreliability of ambient light detection

Core Design Contradiction:

Illumination intensityVSReliability

Solution Approach 1:

The control unit temporarily reduces the luminous intensity of the display before acquiring the detection value from the light sensor. This preliminary action ensures that the display light does not interfere with the ambient light detection, allowing the light sensor to accurately detect ambient light intensity without contamination from the display itself.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The luminous intensity of the display is dynamically adjusted based on the detection requirements. The control unit switches between different luminous intensity levels (first and second levels) depending on whether ambient light detection is needed or display visibility is the priority, creating a dynamic adaptation to different operational states.

Inventive Principle:

Principle #15Dynamics

2Reliability

If the luminous intensity of the display is reduced to improve ambient light detection accuracy, then the reliability of light intensity detection is improved, but the display brightness decreases

Engineering Contradiction:

Improvereliability of light intensity detectionVSAvoidluminous intensity of display

Core Design Contradiction:

ReliabilityVSIllumination intensity

Solution Approach 1:

The control unit temporarily reduces the luminous intensity of the display before acquiring the detection value from the light sensor. This preliminary action ensures that the display light does not interfere with the ambient light detection, allowing the light sensor to accurately detect ambient light intensity without contamination from the display itself.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The luminous intensity of the display is dynamically adjusted based on the detection requirements. The control unit switches between different luminous intensity levels (first and second levels) depending on whether ambient light detection is needed or display visibility is the priority, creating a dynamic adaptation to different operational states.

Inventive Principle:

Principle #15Dynamics

3Adaptability or versatility

If the light sensor is located on the opposite side of the display to enable ambient light detection, then the detection function is improved, but the display light contributes more to the detection value when display luminance is high

Engineering Contradiction:

Improveambient light detection functionVSAvoidaccuracy of ambient light detection

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The control unit temporarily reduces the luminous intensity of the display before acquiring the detection value from the light sensor. This preliminary action ensures that the display light does not interfere with the ambient light detection, allowing the light sensor to accurately detect ambient light intensity without contamination from the display itself.

Inventive Principle:

Principle #10Preliminary action

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 improves the reliability of light intensity detection by reducing the display's impact on the sensor's readings, allowing for more accurate control of display brightness based on ambient light conditions.

Implementation Method 1

a light sensor located on an opposite side of a display surface of the display, and detects intensity of ambient light

Methodology Applied

Scientific EffectLight detection: Photoelectric Effect

Data Source

PatentUS10891918B2Electronic apparatus having function to reduce luminous intensity of display and detect intensity of ambient light in state in which luminous intensity of display is reduced, and light intensity detection method and storage medium storing light intensity detection program having same

Publication Date: 2021.01.12 CASIO COMPUTER CO LTD

AI summary

An electronic apparatus includes: a display; a light sensor located on an opposite side of a display surface of the display, and detects intensity of ambient light; and a control unit, in a first state in which luminous intensity of the display is not less than a first threshold, in the case where the intensity of ambient light detected by the light sensor is less than predetermined intensity of light, outputs, to the display, a signal to reduce the luminous intensity of the display to a second state that is not more than a second threshold that is less than the first threshold, and in the second state, outputs a signal to detect the intensity of ambient light to the light sensor.