Vergence Distance Calculator
Ideal symmetric binocularvergenceintersectiondistancefromactualIPDandTOTALconvergenceangle, D=IPD/[2tan(θ/2)],0<θ<180°, not accommodation reciprocal.
Description
Vergence is the inward rotation of the eyes toward a common target.
Vergence is the inward rotation of the eyes toward a common target.1
A symmetric binocular geometry relates total convergence angle and interpupillary distance to target distance. The calculation and input requirements are explained below.
When to use Vergence Distance Calculator
Enter positive interpupillary distance in mm and total binocular convergence angle strictly between 0 and 180 degrees.
How to use Vergence Distance Calculator and how it works
- Prepare the measurements or independently established model inputs described below, with matching units and observation scope.
- Enter the required fields and run Vergence Distance Calculator.
- Read the result fields using the formula, output units, signs and ordering explained below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualInterpupillaryDistanceMm | Actual Interpupillary Distance Mm. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
| actualTotalVergenceAngleDegrees | Actual Total Vergence Angle Degrees. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
Enter positive interpupillary distance in mm and total binocular convergence angle strictly between 0 and 180 degrees. Convert IPD to meters and divide by twice the tangent of half the angle. Return symmetric geometric target distance in meters.
distanceM=(ipdMm/1000)/(2*tan(totalAngleDegrees*pi/360)) Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.value | Numeric result under the formula and output units explained above. | number |
{
"input": {
"actualInterpupillaryDistanceMm": 60,
"actualTotalVergenceAngleDegrees": 90
},
"output": {
"result": {
"value": 0.030000000000000002
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Vergence Accommodation Conflict Calculator for a complementary operation: Vergence and accommodation describe eye alignment and optical focus respectively.
Use Accommodation Distance Calculator for a complementary operation: Accommodation distance is the reciprocal of optical power on the positive-focus branch.
References
-
Vergence Distance Calculator — tool.io
Similar or alternative tools
- Vergence Accommodation Conflict Calculator
Vergence and accommodation describe eye alignment and optical focus respectively.
- Accommodation Distance Calculator
Accommodation distance is the reciprocal of optical power on the positive-focus branch.