Bar Code Reader Motion Blur Deblurring via Variable Exposure

Solution Overview

Problem

Bar code readers often fail to read bar codes due to motion blur, requiring time-consuming and costly processes to estimate and correct for motion blur, which interrupts workflows in retail and shipping environments.

Innovation Solution

A bar code reader system that captures motion invariant images using a camera and processor, deblurring images without estimating motion blur, ensuring consistent and accurate reading regardless of object motion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional bar code reading methods are used, then the system is simple and easy to operate, but motion blur causes reading failures and requires time-consuming re-reading

Engineering Contradiction:

Improvebar code reading success rateVSAvoidtime for re-reading bar codes

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The system performs preliminary actions by capturing multiple images at different exposure times before the bar code becomes unreadable due to motion. By taking a series of images with varying exposure durations (including at least one image with exposure time greater than 1/500 second), the system ensures that at least one readable image is captured before the bar code moves out of readable range, thereby preventing reading failures and eliminating the need for time-consuming re-reading.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes the exposure time parameter dynamically by capturing images at multiple different exposure times (including at least one image with exposure time greater than 1/500 second). This parameter variation allows the system to capture bar code images under different motion conditions, ensuring that at least one image remains readable even when the bar code is in motion, thus improving reading reliability without requiring re-reading.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If multiple images are captured at different exposure times, then motion blur is reduced and reading accuracy improves, but the device complexity and processing requirements increase

Engineering Contradiction:

Improvebar code image clarityVSAvoidimage capture and processing system

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The system performs preliminary actions by capturing multiple images at different exposure times before the bar code becomes unreadable due to motion. By taking a series of images with varying exposure durations (including at least one image with exposure time greater than 1/500 second), the system ensures that at least one readable image is captured before the bar code moves out of readable range, thereby preventing reading failures and eliminating the need for time-consuming re-reading.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes the exposure time parameter dynamically by capturing images at multiple different exposure times (including at least one image with exposure time greater than 1/500 second). This parameter variation allows the system to capture bar code images under different motion conditions, ensuring that at least one image remains readable even when the bar code is in motion, thus improving reading reliability without requiring re-reading.

Inventive Principle:

Principle #35Parameter changes

3Use of energy by moving object

If images with longer exposure times are used, then more light is captured and bar codes in motion are readable, but motion blur increases and reading accuracy decreases

Engineering Contradiction:

Improvelight capture capabilityVSAvoidbar code image sharpness

Core Design Contradiction:

Use of energy by moving objectVSMeasurement precision

Solution Approach 1:

The system performs preliminary actions by capturing multiple images at different exposure times before the bar code becomes unreadable due to motion. By taking a series of images with varying exposure durations (including at least one image with exposure time greater than 1/500 second), the system ensures that at least one readable image is captured before the bar code moves out of readable range, thereby preventing reading failures and eliminating the need for time-consuming re-reading.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes the exposure time parameter dynamically by capturing images at multiple different exposure times (including at least one image with exposure time greater than 1/500 second). This parameter variation allows the system to capture bar code images under different motion conditions, ensuring that at least one image remains readable even when the bar code is in motion, thus improving reading reliability without requiring re-reading.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS8702003B2Bar code readers and methods of reading bar codes

Publication Date: 2014.04.22 HONEYWELL INTERNATIONAL INC

AI summary

Bar code readers and methods of reading bar codes are described herein. One device includes a camera configured to produce a motion invariant image of a bar code while the bar code is in motion and a processor configured to deblur the motion invariant image of the bar code.