Projection Light Control for 3D Measurement Accuracy

Solution Overview

Problem

Existing three-dimensional measurement techniques using active methods face challenges in achieving stable and high-accuracy distance measurement due to non-uniform reflected light from target objects, leading to suboptimal intensity of projection light.

Innovation Solution

An information processing apparatus and method that determine the amount of projection light for each traveling direction based on the location and orientation of the target object, ensuring the intensity of reflected light falls within a predetermined range by calculating the distance and incident angle, allowing for precise adjustment of projection light to optimize image contrast and measurement accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the amount of projection light is increased to improve reflected light intensity, then measurement precision is improved, but the reflected light may exceed the camera's dynamic range causing saturation

Engineering Contradiction:

Improvedistance measurement accuracyVSAvoidreflected light intensity

Core Design Contradiction:

Measurement precisionVSIllumination intensity

Solution Approach 1:

The patent applies local quality by determining projection light amounts for respective traveling directions based on incident regions and their distances from the projection apparatus. Each direction receives customized light intensity control, allowing regions requiring higher intensity to receive more light while keeping regions with sufficient intensity at lower levels, thus preventing overall saturation while ensuring adequate illumination for accurate measurement

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the parameter of projection light amount dynamically based on distance information and incident region analysis. By calculating required light amounts for each traveling direction and adjusting projection intensity accordingly, the system maintains reflected light within the camera's dynamic range while optimizing measurement precision across different spatial regions

Inventive Principle:

Principle #35Parameter changes

2Illumination intensity

If the amount of projection light is decreased to avoid exceeding camera dynamic range, then saturation is prevented, but measurement precision deteriorates due to insufficient reflected light intensity

Engineering Contradiction:

Improvereflected light intensity within dynamic rangeVSAvoiddistance measurement accuracy

Core Design Contradiction:

Illumination intensityVSMeasurement precision

Solution Approach 1:

The patent applies local quality by determining projection light amounts for respective traveling directions based on incident regions and their distances from the projection apparatus. Each direction receives customized light intensity control, allowing regions requiring higher intensity to receive more light while keeping regions with sufficient intensity at lower levels, thus preventing overall saturation while ensuring adequate illumination for accurate measurement

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the parameter of projection light amount dynamically based on distance information and incident region analysis. By calculating required light amounts for each traveling direction and adjusting projection intensity accordingly, the system maintains reflected light within the camera's dynamic range while optimizing measurement precision across different spatial regions

Inventive Principle:

Principle #35Parameter changes

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 enables stable and high-accuracy distance measurement by ensuring the intensity of reflected light is within the dynamic range of the camera, enhancing the contrast of the distance measurement pattern and improving measurement precision.

Implementation Method 1

measuring reflected light from the target object

Methodology Applied

Scientific EffectReflection: Reflection

Data Source

PatentUS9560250B2Information processing apparatus, measurement system, control system, light amount determination method and storage medium

Publication Date: 2017.01.31 CANON KK

AI summary

There is provided with an information processing apparatus. Location information indicating an approximate location of a measurement target relative to a projection apparatus is obtained. The projection apparatus projects, onto the measurement target, projection light of a predetermined pattern composed of light rays travelling in respective directions. For respective travelling directions, incident regions of the measurement target on which the projection light is incident are estimated in accordance with the location information. Amounts of the projection light toward the respective travelling directions are determined such that light amounts of reflected light from the estimated incident regions toward an image capturing apparatus fall within a predetermined range. The image capturing apparatus captures an image of the measurement target onto which the projection light has been projected.