Understanding Lighting Concepts

  • A well planned machine vision lighting application is designed to maximize feature contrast, while minimizing contrast of the rest.

  • Images with poor contrast and uneven illumination require more effort from the imager, increasing process time.

  • High contrast features simplify integration and improve reliability.

  • Variation of the part and environment should not affect the results.

Effective lighting maximizes feature contrast


In each example, the same part, camera and lens are used. Different light makes the vision processing harder or easier.


          
 

 

Three elements are needed to make an image:
  • Camera: It looks at the reflected light, not at the part


  • Part: It can reflect light in many ways, so look at the part features


  • Illumination: Broad-band, monochromatic light source (i.e. NERLITE products)