Description
Apply a supplied retinal research image angular calibration, without inferring retinal anatomy or disease.
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.
Apply a supplied retinal research image angular calibration, without inferring retinal anatomy or disease.
When to use this tool
Use Retinal Pixel Angle 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 pixels, radiansPerPixel. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read angleRadians. Use the output convention below.
For nonnegative pixels and positive radiansPerPixel return angleRadians=pixels*radiansPerPixel.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| pixels | Pixels | Required. Finite number; minimum 0. |
| radiansPerPixel | Radians Per Pixel | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| angleRadians | Angle Radians | Required. Finite number. |
{
"input": {
"pixels": 120,
"radiansPerPixel": 0.001
},
"output": {
"angleRadians": 0.12
}
}Limitations and assumptions
- Pixels is a supplied extent and may be fractional. The linear angular scale is assumed, not derived from optics, device calibration, retinal geometry, or a clinical reference.
- 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
- Retinal Image Angle Length Factor
Supplied reduced-eye planar scale times angle or tangent, without an individual eye biometry or retinal magnification model.
- Eye Tracker Screen Gaze Angle Term
Flat-screen geometric gaze offsets from explicitly calibrated coordinates and viewing distance, not an eye-tracker calibration or diagnosis.