KNOWLEDGE CENTER
Optical Distortion Guide
Understand barrel distortion, pincushion distortion, and perspective effects in machine vision systems. Learn how optical distortion impacts measurement accuracy and how to select the right lens for precision imaging applications.
What Is Optical Distortion?
Optical distortion is an imaging error that causes straight lines in the real world to appear curved or displaced in an image.
Unlike blur or focus issues, distortion changes the geometric accuracy of an image. In machine vision applications, excessive distortion can reduce measurement precision, object positioning accuracy, and image consistency.
Distortion becomes especially important in applications such as dimensional inspection, robotic guidance, metrology, and automated measurement systems.

Why Distortion Matters
Measurement Accuracy
Robot Positioning
Inspection Reliability
Common Types of Optical Distortion
Barrel Distortion

Pincushion Distortion

Mustache Distortion

Perspective Distortion

How Distortion Changes an Image

How Optical Distortion Is Measured
Optical distortion is commonly expressed as a percentage value that indicates how much image geometry deviates from an ideal projection.
Lower distortion values provide more accurate geometric representation and are preferred for precision machine vision systems.
| Distortion Level | Performance |
|---|---|
| <0.1% | Excellent |
| 0.1%-0.5% | Very Good |
| 0.5%-1% | Acceptable |
| >1% | May Require Correction |
Distortion Requirements by Application
| Application | Recommended Distortion |
|---|---|
| Dimensional Measurement | <0.1% |
| Metrology | <0.05% |
| PCB Inspection | <0.1% |
| Robot Guidance | <0.5% |
| Security Monitoring | <2% |
| Traffic Monitoring | <2% |
Related Vision Solutions
How to Minimize Optical Distortion
Distortion Performance of Common Lens Types
| Lens Type | Typical Distortion |
|---|---|
| Standard FA Lens | 0.1% - 1% |
| Low Distortion Lens | <0.1% |
| Telecentric Lens | Near 0% |
| Wide-Angle Lens | 1% - 10% |
| Fisheye Lens | 10%+ |
Frequently Asked Questions
Related Optical Knowledge
Looking for Low-Distortion Machine Vision Lenses?
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