Switchable Diffuser for 3D Projection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current light projecting technologies are hindered by high costs, large size, and low integration, as they often require multiple light sources and projection systems to achieve desired functionalities, such as 3D feature detection and mapping, which is inefficient and unsuitable for small environments.

Innovation Solution

A light projecting system utilizing a switchable diffuser that can change between flood light and collimated light projection states by oscillating an applied voltage, allowing for time-division multiplexed emission of both light types from a single light source, enabling efficient 3D feature detection and mapping without the need for multiple light sources.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple light sources and projection subsystems are deployed to achieve both flood light illumination and dot projection, then the desired 3D feature detection and mapping functionality is achieved, but the system size increases and integration becomes difficult

Engineering Contradiction:
Improvelight projection functionalityVSAvoidsystem size
Core Design Contradiction:
Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The patent combines flood light illumination and dot projection functionalities into a single light source and projection subsystem. The switchable diffuser element allows one light source to perform multiple functions by changing its light distribution pattern between broad beam (flood light) and narrow beam (dot projection) modes, thereby reducing system size and improving integration while maintaining versatile 3D feature detection and mapping capabilities

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The projection subsystem is designed with multi-functionality, where a single light source can operate in different modes (flood light and dot projection) through the switchable diffuser. This universal design allows the same hardware to serve multiple purposes: illumination for image capture and structured light projection for 3D mapping, eliminating the need for separate dedicated components

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

2Adaptability or versatility

If multiple light sources are used to achieve flood light and dot projection, then both illumination and structured light functions are achieved, but the device complexity increases

Engineering Contradiction:
Improvelight projection capabilityVSAvoidsystem complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent merges multiple light projection functions into a single integrated subsystem with a switchable diffuser element. This consolidation reduces device complexity by eliminating redundant components and control systems while maintaining the ability to switch between flood light and dot projection modes as needed for different 3D detection tasks

Inventive Principle:
Principle #5Merging (Combining)

3Ease of manufacture

If conventional light projecting technologies are used, then basic light projection is achieved, but cost increases and integration with existing light sources is poor

Engineering Contradiction:
Improveintegration efficiencyVSAvoidlight source utilization
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The invention creates a universal projection subsystem that can work with existing light sources and perform multiple functions (flood light illumination and dot projection). This improves ease of manufacture and integration by allowing the system to leverage already available light sources while adding versatile projection capabilities through the switchable diffuser mechanism

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

This solution reduces the complexity and size of light projection systems, enhancing integration and efficiency while maintaining the capability for 3D feature detection and mapping, making it suitable for various applications including mobile devices and small environments.

Implementation Method 1

a switchable diffuser having a first surface and a second surface, the switchable diffuser coupled to a control source and configured to change from a first state to a second state responsive to the control source being changed from a first condition to a second condition; wherein in the first state the switchable diffuser is configured to receive at least a portion of the plurality of collimated beams of light at the first surface and project a flood light out of the second surface; wherein in the second state the switchable diffuser is configured to permit at least a portion of the plurality of collimated beams of light to propagate out of the second surface as an array

Methodology Applied
Scientific EffectSwitchable diffuser effect:

Data Source

PatentEP3910408B1Optical projection system and method
Publication Date: 2023.05.10 SHENZHEN GUANGJIAN TECH CO LTD
  • EP3910408B1 patent drawingFigure 1
  • EP3910408B1 patent drawingFigure 2
  • EP3910408B1 patent drawingFigure 3A

AI summary

A system including a light projecting system configured to project collimated beams of light; and a switchable diffuser. The switchable diffuser is coupled to a control source. The switchable diffuser changes from a first state to a second state responsive to the source being changed from a first condition to a second condition (e.g., changing a voltage condition from 0V to 1-50V). In the first state, the switchable diffuser receives collimated beams of light, diffuses them and projects a flood light. In the second state, the switchable diffuser is substantially transparent to the plurality of collimated beams of light, and permits the collimated beams of light to propagate through and out as an array. Systems may also include a detector configured to capture flood light and dot array reflections, and/or a ToF detector configured to measure time differences between different portions of returning light reflected off of a surface.