Through-Display Proximity Sensing for Edge-to-Edge Emissive Displays

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Solution Overview

Problem

Existing displays fail to effectively address the challenge of extending the emissive area of a display towards the edges of a mobile device without compromising space for proximity sensors or other optical devices, leading to inefficient use of display real estate.

Innovation Solution

A proximity sensor that includes a transmitter configured to transmit electromagnetic radiation through the display and a receiver to receive electromagnetic radiation reflected off objects, generating a quantitative output signal based on the amount of electromagnetic radiation received, and a processor to deactivate or activate the touchscreen and/or the emissive display when the sensor is configured to transmit a first predetermined amount of light when the distance is greater than a near threshold distance and a second predetermined amount when the distance is less than the near threshold distance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of moving object

If the emissive area of the display is expanded to cover more area of the mobile device, then the display area is improved, but the space for proximity sensors and other optical devices deteriorates

Engineering Contradiction:
Improveemissive area of the displayVSAvoidspace for proximity sensors
Core Design Contradiction:
Area of moving objectVSArea of stationary object

Solution Approach 1:

The proximity sensor is integrated behind the display, merging the sensor functionality with the display structure. The transmitter and receiver are positioned on opposite sides of the display, allowing the display to serve as both the visual output medium and the optical path for proximity detection, thus eliminating the need for separate sensor space.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The proximity sensor is moved from the traditional side-mounted position to a behind-display position, utilizing the z-dimension (depth) rather than the x-y plane. This dimensional transition allows the display area to be fully utilized while the sensor operates through the display thickness, resolving the spatial conflict between display area and sensor space.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If the proximity sensor transmits light through the display to detect objects, then the proximity detection function is improved, but the display uniformity deteriorates due to the openings required in the opaque layer

Engineering Contradiction:
Improveproximity detection functionVSAvoiddisplay uniformity
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The opaque layer is designed with localized openings only in the specific regions where proximity detection is needed, rather than being uniformly transparent or opaque. This allows the display to maintain its uniform appearance in most areas while providing targeted optical access for the proximity sensor where required.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The opaque layer with openings acts as an intermediary between the display and the proximity sensor. It selectively allows light transmission in specific regions while blocking light in other regions, mediating between the need for proximity detection and the need for display uniformity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Measurement precision

If the transmitter increases the amount of transmitted light when the object is very close to the display, then the detection accuracy is improved, but the energy consumption increases

Engineering Contradiction:
Improvedetection accuracyVSAvoidenergy consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The transmitter dynamically adjusts its light output based on the detected proximity of objects. When an object is detected close to the display, the transmitter increases its light transmission to maintain detection accuracy. This dynamic adjustment optimizes the balance between detection precision and energy consumption by transmitting more light only when necessary.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The proximity sensor system uses feedback from the received light signal to control the transmitter output. When the received signal indicates an object is very close, the system feeds back to increase transmitter power to maintain accurate detection, and reduces power when objects are farther away, optimizing energy usage based on real-time conditions.

Inventive Principle:
Principle #23Feedback

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

Enables the extension of the emissive area of the display to the edges of the mobile device without the need for additional space, accurately detecting proximity to objects and activating/deactivating the touchscreen and/or display based on the quantitative output signal.

Implementation Method 1

a transmitter configured to transmit electromagnetic radiation through the display

Methodology Applied
Scientific EffectElectromagnetic radiation transmission: Light

Implementation Method 2

receive electromagnetic radiation transmitted by the transmitter, reflected off an object facing the emissive display

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 3

a receiver of electromagnetic radiation configured to receive electromagnetic radiation transmitted by the transmitter, reflected off an object facing the emissive display and received through the emissive display

Methodology Applied
Scientific EffectElectromagnetic radiation reception: Photoelectric Effect

Data Source

PatentEP4168886B1Emissive display configured with through-display zero-distance proximity sensor
Publication Date: 2025.12.24 GOOGLE LLC
  • EP4168886B1 patent drawingFigure 1A~1B
  • EP4168886B1 patent drawingFigure 2A~2B
  • EP4168886B1 patent drawingFigure 3A

AI summary

A mobile computing device an emissive display that includes a touchscreen and a proximity sensor. The proximity sensor includes a transmitter configured to transmit electromagnetic radiation through the display and a receiver of electromagnetic radiation configured to receive electromagnetic radiation transmitted by the transmitter, reflected off an object facing the emissive display and received through the emissive display. The proximity sensor is configured for generating a quantitative output signal based on an amount of the received electromagnetic radiation, and the transmitter is configured to transmit a first predetermined amount of light when a distance between the object and the display is greater than a near threshold distance between the object and the display and is configured to transmit a second predetermined amount of light when the distance between the object and the display is less than the near threshold distance. The second predetermined amount is greater than the first predetermined amount. A processor is configured for receiving the generated quantitative output signal, and memory stores instructions that, when executed by the processor, cause the processor to deactivate the touchscreen and/or the emissive display when the touchscreen and/or the emissive display is activated and when the quantitative output signal increases above an high threshold value and to activate the touchscreen and/or the emissive display when the touchscreen and/or the emissive display is deactivated and when the quantitative output signal is below a low threshold value, the low threshold value being less than the high threshold value.