Selecting a Machine Vision Lens
Selecting the correct machine vision lens is a science. There are many factors to consider. Some key lens criteria include:
- Contrast: Delivering light contrast to the sensor
- Resolution: Delivering object detail to the sensor
- Depth of Field: Depth range in which the object will be in focus
- Field of View: Area imaged by a lens
- Working Distance: Distance between the lens face and the object
- Distortion: The many aberrations that modify your otherwise perfect image
- Mount: Most cameras are compatable with C-mount lenses, but be sure to confirm
- Size: Most cameras are compatible with 2/3 size (11 mm diagonal) lenses, but some require a lens having a larger 'optical circle'.
- Cost (No point in spending more than necessary to get the required performance)
Most of these critiera are intrinsically connected, and there is no value in considering one outside the context of the rest. Lens selection is often a compromise between many competing factors. And it is all too easy to limit your camera's performance by using the wrong lens.
So, how do you select the appropriate lens for your application? First consider the general type of lens you need. You may use the table below as a rough guide.
|Object Width||Lens Type||Calculator|
|> 12 mm||General Purpose Lens||Entrocentric Lens Calculator|
|1 - 25 mm||Macro Lens||Macro Lens Calculator|
|< 1 mm||Microscopic Lens|
|Precision Gauging 1 - 240 mm||Telecentric Lens||Telecentric Lens Calculator|
Contact us for a lens recommendation.