Have you integrated a vision system lately, and noticed some changes in its performance from one day to another?  One tends to look for a problem related to the parts themselves – the difference might lie in the variations from one batch to another. But if you haven’t paid close attention to the light during your vision system integration, you might be surprised at how much it can influence your system’s performance. A vision system close to a window could work well on a rainy day but have various problems on a sunny day… That is, if you haven’t put in place effective measures to limit the impact of ambient light. Or the system could output weird results if you have not selected the appropriate lighting.

Audrey Boucher-Genesse, from Robotiq, talks about how important light is in a vision system. Light is used to:

  1. Maximize the contrast on the features of interest
  2. Minimize the contrast elsewhere

The better the contrast will be, the easier it will be afterward to process your image.

Dark Field Effect and Bright Field Effect

Dark field effect and bright field effect
Dark field effect (top) and bright field effect (bottom) (Source: Robotiq)

This article covers:

  • Dark field and Bright Field
  • What Type of Light Should I Be Using?
  • Ambient Light Is Important

> Read more by Audrey Boucher-Genesse, Robotiq, August 23, 2016

 

 

Light: the Key to a Successful Machine Vision Application