Machine Vision Pixel Resolution Calculator
Enter the camera resolution, sensor size, field of view and the smallest defect. The tool returns the object-side sampling and the resolution needed to reach your sampling target.
Calculator
Formula and applicable conditions
| Object-side pixel size | p_obj = (sensor width / pixels_H) / β where β = sensor width / FOV width |
|---|---|
| Defect coverage | n = defect size / p_obj |
| Required horizontal pixels | pixels_H = FOV width / (defect size / target pixels) |
Parameter definitions
| Camera resolution | Active pixels across the sensor width. |
|---|---|
| Effective sensor size | Imaging area in mm, from the camera datasheet. |
| Field of view | Object area covered by one image. |
| Defect size | Smallest feature to detect, in µm. |
| Target pixels on defect | Desired number of pixels across the smallest feature. |
Worked example
- FOV 50 mm, defect 10 µm, target 3 pixels: required horizontal pixels = 50 / (0.010 / 3) = 15 000 px.
- With a 1-inch sensor (12.8 mm) and a 5 MP camera (2592 px), the object-side pixel size is 12.8 / 2592 / (12.8 / 50) = 19.3 µm/px, so a 10 µm defect covers only 0.5 pixels.
- The conclusion: this camera cannot sample the defect; either raise magnification (smaller FOV) or use a line scan / multi-camera setup.
Frequently asked questions
Is 3 pixels on a defect enough to detect it?
Three pixels is a common sampling rule of thumb for detection, not a guarantee. Real detectability depends on optical MTF, contrast, illumination, sensor noise and the inspection algorithm.
Why does the tool separate sampling from accuracy?
Sampling describes how finely the object is discretised. Accuracy describes how close a measurement is to the true value and depends on calibration and the whole error budget. They are different quantities.
Can I reach the target by increasing resolution only?
Higher resolution helps only if the optics can actually resolve the detail and if illumination and contrast are sufficient. Check the lens resolution stated in the datasheet before specifying a higher-resolution camera.
Which POMEAS cameras are listed?
Only cameras whose parameters were transcribed from an official POMEAS datasheet. Models without a readable datasheet are not listed.
Request a POMEAS lens recommendation
Submit the parameters and the calculation result below. The form posts to the existing POMEAS contact interface; nothing is sent automatically and no data is shared with third parties.