Description
Propagate supplied bounded edge-location errors into a diameter interval, without estimating blur from an image.
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.
Propagate supplied bounded edge-location errors into a diameter interval, without estimating blur from an image.
When to use this tool
Use Pupil Edge Blur Uncertainty Term 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 diameter, leftEdgeHalfWidth, rightEdgeHalfWidth. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read lower, upper, halfWidth. Use the output convention below.
For nonnegative diameter and edge halfwidths require diameter>=leftEdgeHalfWidth+rightEdgeHalfWidth. Return halfWidth as their sum and lower/upper=diameter minus/plus halfWidth.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| diameter | Diameter | Required. Finite number; minimum 0. |
| leftEdgeHalfWidth | Left Edge Half Width | Required. Finite number; minimum 0. |
| rightEdgeHalfWidth | Right Edge Half Width | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| lower | Lower | Required. Finite number. |
| upper | Upper | Required. Finite number. |
| halfWidth | Sum of the two absolute edge halfwidths, not root-sum-square uncertainty. | Required. Finite number. |
{
"input": {
"diameter": 5,
"leftEdgeHalfWidth": 0.1,
"rightEdgeHalfWidth": 0.2
},
"output": {
"lower": 4.7,
"upper": 5.3,
"halfWidth": 0.30000000000000004
}
}Limitations and assumptions
- Use one length unit. These are additive supplied edge-error bounds, not independent standard uncertainties or a confidence interval; image blur, actual pupil diameter, and clinical implications are not estimated.
- 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
- Pupil Ellipse Axis Ratio
For positive majorAxis and minorAxis within zero through majorAxis return axisRatio=minorAxis/majorAxis.
- Astigmatic Power One Meridian Term
Paraxial sphero-cylinder meridian power S+C*sin²(theta-axis) in radians, without a prescription recommendation.