Distance Sensing Assembly With Reflective-Mirror Light Routing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing implementation of distance sensors in mobile terminals reduces the screen-to-body ratio and aesthetic appeal by occupying display area due to the need for openings for infrared light emission and reception, hindering the development of full-screen designs.

Innovation Solution

A distance sensing assembly that employs an emitter array, receiver array, and reflective mirror or light guide columns below the cover plate to redirect infrared light, allowing distance detection without additional openings in the display region, thereby increasing the screen-to-body ratio and improving display performance and aesthetics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an opening is formed in the display region for distance sensor operation, then distance detection function is achieved, but the screen-to-body ratio and aesthetic appeal are reduced

Engineering Contradiction:
Improvedistance detection functionVSAvoiddisplay area
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The patent moves the distance sensor from the front display region to the bottom edge of the device, utilizing the vertical dimension and edge space instead of compromising the horizontal display area. This dimensional relocation allows the sensor to operate without creating openings in the display region, thereby maintaining both the distance detection function and the screen-to-body ratio.

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

Solution Approach 2:

The patent introduces a reflective mirror as an intermediary element that redirects infrared light from the bottom edge location to the distance sensor. This mediator enables the sensor to receive infrared light effectively despite being positioned away from the direct emission path, resolving the contradiction between sensor positioning and functional effectiveness.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Area of stationary object

If the distance sensor is positioned below the display region, then the screen-to-body ratio is improved, but the infrared light path for sensor operation becomes problematic

Engineering Contradiction:
Improvedisplay areaVSAvoidinfrared light path configuration
Core Design Contradiction:
Area of stationary objectVSDevice complexity

Solution Approach 1:

The reflective mirror serves as an intermediary that simplifies the infrared light path configuration by redirecting light from the bottom edge to the distance sensor. This mediator element makes the relocated sensor position functional without significantly increasing overall device complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent segments the infrared light path into distinct functional zones: the emission area at the bottom edge, the reflection area with the mirror, and the reception area at the distance sensor. This segmentation allows each component to be optimized independently while working together as an integrated system.

Inventive Principle:
Principle #1Segmentation

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 accurate distance detection without occupying display area, enhancing the screen-to-body ratio and aesthetic appeal of mobile terminals by redirecting infrared light paths using reflective mirrors and light guide columns.

Implementation Method 1

an orthographic projection of the reflective mirror on a plane of the cover plate covers at least a portion of a gap between the cover plate and an earpiece of the mobile terminal. Infrared light emitted by the emitter array passes, after being reflected by the reflective mirror, through the gap

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

A distance sensing assembly that employs an emitter array, receiver array, and reflective mirror or light guide columns below the cover plate to redirect infrared light

Methodology Applied
Scientific EffectLight guidance: Waveguide (optics)

Data Source

PatentEP3564700B1Distance sensing assembly and mobile terminal
Publication Date: 2025.10.01 BEIJING XIAOMI MOBILE SOFTWARE CO LTD
  • EP3564700B1 patent drawingFigure 1~2
  • EP3564700B1 patent drawingFigure 3~4
  • EP3564700B1 patent drawingFigure 5~6

AI summary

The present disclosure discloses a distance sensing assembly and a mobile terminal, and relates to the field of electronic technologies. The distance sensing assembly includes: an emitter array (1), a receiver array (2) and a reflective mirror (3). The emitter array (1), the receiver array (2) and the reflective mirror (3) are located below a cover plate (4) of the mobile terminal. An orthographic projection of the reflective mirror (3) on a plane of the cover plate (4) covers at least a portion of a gap (5) between the cover plate (4) and an earpiece of the mobile terminal. Infrared light emitted by the emitter array (1) passes, after being reflected by the reflective mirror (3), through the gap (5) to be emitted out; and the receiver array (2) receives the infrared light which is reflected, after passing through the gap (5), by the reflective mirror (3).