Structured Light Projector Illuminator Brightness Uniformity

Solution Overview

Problem

Existing structured light projectors face challenges in achieving uniform brightness across the cross-section of structured light due to optical component distortions, which affects the precision of 3D shape recognition and object identification.

Innovation Solution

A structured light projector design that includes an illuminator with multiple illumination areas, each emitting light with different intensities and durations, and featuring light-emitting elements with varying densities and aperture diameters, to compensate for lens distortions and ensure uniform brightness across the structured light pattern.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If uniform light intensity is emitted from all illumination areas, then the manufacturing is simple, but lens distortion causes non-uniform brightness in the projected structured light

Engineering Contradiction:

Improvebrightness uniformity of structured lightVSAvoidcomplexity of light emission control

Core Design Contradiction:

Illumination intensityVSDevice complexity

Solution Approach 1:

The patent applies local quality by assigning different light emission characteristics to different illumination areas based on their position. Specifically, peripheral illumination areas emit light with higher intensity and/or longer duration compared to central illumination areas, compensating for the greater distortion effect on peripheral regions. This localized differentiation ensures uniform brightness across the projected structured light pattern.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent implements preliminary anti-action by pre-compensating for lens distortion through unequal light emission. Before projection, the system intentionally creates non-uniform light emission from the illuminator, with peripheral areas emitting more light than central areas. This preliminary adjustment counteracts the distortion that will occur during projection, resulting in uniform brightness in the final structured light pattern.

Inventive Principle:

Principle #9Preliminary anti-action

2Measurement precision

If the illuminator emits equal light intensity from all areas, then the energy consumption is low and control is simple, but the 3D sensing precision deteriorates due to non-uniform brightness

Engineering Contradiction:

Improve3D shape recognition precisionVSAvoidenergy consumption of illuminator

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies local quality by assigning different light emission characteristics to different illumination areas based on their position. Specifically, peripheral illumination areas emit light with higher intensity and/or longer duration compared to central illumination areas, compensating for the greater distortion effect on peripheral regions. This localized differentiation ensures uniform brightness across the projected structured light pattern.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent implements preliminary anti-action by pre-compensating for lens distortion through unequal light emission. Before projection, the system intentionally creates non-uniform light emission from the illuminator, with peripheral areas emitting more light than central areas. This preliminary adjustment counteracts the distortion that will occur during projection, resulting in uniform brightness in the final structured light pattern.

Inventive Principle:

Principle #9Preliminary anti-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

The solution ensures uniform brightness of structured light, enhancing the precision of 3D sensing and object recognition by adjusting light emission based on lens distortion, thereby improving the accuracy of 3D shape recognition and object identification.

Implementation Method 1

The first light-emitting element and the second light-emitting element may include vertical cavity surface emitting lasers (VCSELs), respectively

Methodology Applied

Scientific EffectVertical cavity surface emitting laser (VCSEL):

Implementation Method 2

a pattern mask comprising a plurality of areas, the pattern mask being configured to generate structured light from light emitted by the illuminator based on a pattern of the pattern mask

Methodology Applied

Scientific EffectDiffraction: Diffraction

Implementation Method 3

a lens configured to project the structured light

Methodology Applied

Scientific EffectRefraction: Refraction

Data Source

PatentUS11695252B2Structured light projector and electronic apparatus including the same

Publication Date: 2023.07.04 SAMSUNG ELECTRONICS CO LTD

AI summary

Provided are a structured light projector that generates and projects structured light, and an electronic apparatus including the structured light projector. The structured light projector includes an illuminator configured to emit light, a pattern mask configured to form structured light by partially transmitting and partially blocking incident light from the illuminator based on a pattern of the pattern mask, and a lens configured to project the structured light. The illuminator includes a plurality of illumination areas respectively facing a plurality of areas of the pattern mask, wherein intensities of lights respectively emitted by the plurality of illumination areas are different from one other.