Should I enter FOV or focal length?

Enter what you know. Set focal length and working distance to derive FOV and scene size, or enter the required FOV/scene width to back-calculate focal length. The calculator is meant for incomplete early-design inputs.

Does this replace the lens datasheet?

No. It uses a thin-lens geometric model. Real lenses have distortion, chief-ray angle limits, and manufacturer FOV tables. Use this to shortlist options, then verify critical dimensions against the vendor datasheet or MTF charts.

When should I use Camera Placement Planner instead?

Use FOV Calculator to size the lens and confirm mm/px at a working distance. Switch to Placement Planner when you need to position the camera and inspection zone on the belt and check spatial coverage, offsets, and mounting distances.

How is pixel accuracy related to FOV?

Wider scene coverage at the same resolution means coarser mm/px. If inspection needs finer resolution, you must narrow FOV, move closer, use a longer lens, or increase sensor resolution — this tool makes that trade-off visible early.

Machine Vision

Camera Field of View Calculator

Size lens and sensor combinations — solve for FOV, working distance, scene coverage, and magnification. For spatial layout and coverage on the belt, use Camera Placement Planner.

Machine vision workflowStep 2 of 6

Next workflow step

Continue to Pixel Accuracy Calculator — HFOV 19.96° · 400.00 mm WD

Continue

Try an example

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Camera resolution & sensor

Preset

Sensor: 8.8 × 6.6 mm · 2448 × 2048 px

Focal length

Horizontal FOV

Vertical FOV

Working distance

Scene width

Scene height

Magnification

Pixel size (approx.)

mm/px

Compare A vs B

Same sensor and 400 mm working distance. Shorter glass covers more belt and coarsens mm/px.

Metric	A · 16 mm	B · 25 mm(current)
Focal length(mm)	16	25
Horizontal FOV(°)	30.8	20.0
Scene width(mm)	220.0	140.8
Pixel size(mm/px)	0.0899	0.0575
Magnification(×)	0.0417	0.0667

How it works: FOV angles come from sensor size and focal length. Scene width and height use the thin-lens model W = sensor × WD / f. Magnification is f / WD. Pixel size divides scene width by horizontal resolution. Next step: lay out camera position and check coverage.

Learn about this tool

What it is, when to use it, formulas, and common questions

What is this?

This is a bidirectional machine vision field-of-view calculator. Given sensor size, focal length, and working distance, it solves for horizontal/vertical FOV, scene coverage, magnification, and approximate pixel accuracy (mm/px).

Unlike a one-way “enter focal length → get FOV” sheet, you can start from whatever you already know — required scene width, available mount height, or a candidate lens — and back-solve the missing optical parameters before you buy hardware.

When do engineers use it?

Use it during camera and lens selection, when you need to answer: “Will this sensor and lens cover my part at this working distance, and is mm/px good enough for the defect size?”

Typical moments: quoting a vision cell, comparing 1/1.8" vs 2/3" sensors, checking whether a 16 mm vs 25 mm lens fits the belt width, or confirming resolution before algorithm work. Once optics look feasible, move to Camera Placement Planner for physical mount layout on the conveyor.

Formula

HFOV ≈ 2 × atan(sensor_width / (2 × f))
Scene width ≈ 2 × WD × tan(HFOV / 2)
mm/px ≈ scene width ÷ image width (px)
Magnification ≈ sensor_width ÷ scene width

Example

Example: 2/3" sensor (~8.8 mm wide), 25 mm lens, working distance 400 mm.

Horizontal FOV is roughly atan-based from sensor width and focal length; scene width at 400 mm is typically on the order of ~140 mm (exact value depends on the precise sensor active area). If your part is 120 mm wide with margin, it fits. If you need 0.1 mm/px and the camera is 2448 px wide, required scene width ≈ 2448 × 0.1 ≈ 245 mm — so you would need a wider FOV (shorter lens or longer WD), not just a higher-resolution claim on the datasheet.

FAQ

Should I enter FOV or focal length?: Enter what you know. Set focal length and working distance to derive FOV and scene size, or enter the required FOV/scene width to back-calculate focal length. The calculator is meant for incomplete early-design inputs.
Does this replace the lens datasheet?: No. It uses a thin-lens geometric model. Real lenses have distortion, chief-ray angle limits, and manufacturer FOV tables. Use this to shortlist options, then verify critical dimensions against the vendor datasheet or MTF charts.
When should I use Camera Placement Planner instead?: Use FOV Calculator to size the lens and confirm mm/px at a working distance. Switch to Placement Planner when you need to position the camera and inspection zone on the belt and check spatial coverage, offsets, and mounting distances.
How is pixel accuracy related to FOV?: Wider scene coverage at the same resolution means coarser mm/px. If inspection needs finer resolution, you must narrow FOV, move closer, use a longer lens, or increase sensor resolution — this tool makes that trade-off visible early.