Description
Uniform-index slab optical path and excess over a supplied surrounding medium, not a full crystalline-lens model.
Vision research uses stimulus angles, chart notations, image scales, viewing distances, coordinate origins, and observation windows. These quantities have different denominators and measurement conventions. A conversion or support share does not independently establish a visual measurement or its clinical interpretation.
Uniform-index slab optical path and excess over a supplied surrounding medium, not a full crystalline-lens model.
When to use this tool
Use Lens Thickness Optical Path Factor when you need this image, stimulus, notation, coordinate, or observation component for supplied research data.
How to use the tool and how it works
- Enter thickness, refractiveIndex, surroundingIndex. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read opticalPath, excessOpticalPath. Use the output convention below.
For nonnegative thickness and positive refractiveIndex and surroundingIndex return opticalPath=thickness*refractiveIndex and excessOpticalPath=thickness*(refractiveIndex-surroundingIndex).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| thickness | Thickness | Required. Finite number; minimum 0. |
| refractiveIndex | Positive dimensionless index for the modeled path. | Required. Finite number; strictly above 0. |
| surroundingIndex | Positive dimensionless index for the comparison path. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| opticalPath | Optical Path | Required. Finite number. |
| excessOpticalPath | Excess Optical Path | Required. Finite number. |
{
"input": {
"thickness": 5,
"refractiveIndex": 1.5,
"surroundingIndex": 1
},
"output": {
"opticalPath": 7.5,
"excessOpticalPath": 2.5
}
}Limitations and assumptions
- Thickness uses a length unit and indices are dimensionless. This assumes a uniform straight path through the thickness; it does not trace refraction, compute lens power, or validate a clinical optical device.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use calibrated acquisition and a documented visual or imaging protocol for complete interpretation. Confirm the reporting notation, viewing geometry, image scale, and support of the underlying observations.
References
Similar or alternative tools
- Lens Edge Center Thickness Geometry Term
Ideal spherical-surface sagittae with an explicit convex/concave thickness convention; negative edge thickness exposes inconsistent model dimensions.
- Lens Base Curve Supplied Index Crosswalk
Same-curvature refracting-surface power under explicitly supplied indices, without selecting a lens base curve.