1. Lens Type and Size
What is the appropriate lens size and type for your application?
Different types of lenses serve specific purposes in various applications. Board mount lenses are primarily used for small devices and embedded vision applications.
In contrast, C and CS mount lenses are used primarily for machine and security applications. Bayonet mount lenses, on the other hand, are used in applications where a large image sensor is required.
2. Lens mount type
Is the lens the correct mount type and/or thread size to fit your lens mount?
Selecting the correct lens for your mount is critical to lens function. For example, both C and CS type lens mounts share the same diameter and thread size, but a CS lens won’t focus properly on the sensor if it is used in a C type lens mount. A smaller, M12 type mount is shown above.
3. Image circle and sensor size
Does the image circle of the lens provide adequate coverage for the image sensors?
The image circle projected by the lens should provide consistent illumination from the center to the edge of the image sensor.
4. Lens resolution
Does the lens provide sufficient resolution to resolve the details you need to capture?
The resolution of a lens is measured in line pairs per millimeter using charts like the one shown here. The smallest detail you need to resolve should be imaged by at least two pixels on the sensor and should be resolved crisply by the lens you have selected.
5. Focal length and field of view
What focal length is required to capture the right FOV at your working distance?
Your lens will need to have the appropriate focal length to provide the right field of view (FOV) to fill the frame with the object you need to capture at your planned working distance. In general, for a given image sensor size, a shorter focal length provides a wider field of view.