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The six fundamental parameters of machine vision optics


In-Sight 视觉系统


Machine Vision

Manufacturers can speed production, minimize defects and reduce costs with machine vision technologies

Samantha Frost, 08-06-2013

If you are like most people working with machine vision, you’ve probably wondered how different lenses can help you get more and better inspection and defect detection capabilities from your vision system.  How much do you need to spend?  Can you get the resolution you need from a quality but inexpensive lens?  These are good questions and critical to making smart lens choices.

The first thing you need to do is familiarize yourself with the fundamental parameters that influence image quality. This will go a long way to helping maximize the performance of your vision system.

Here are the six principal parameters:

  1. Field Of View: This is the viewable area of the object
  2. Working Distance: The distance from the front of the lens to the object
  3. Resolution: The minimum feature size of the object
  4. Depth Of Field: The maximum object depth that can be maintained entirely in focus
  5. Sensor Size: The size of a camera sensor’s active area, typically specified in the horizontal dimension
  6. Primary Magnification (PMAG):  The ratio between the sensor size and the FOV