Description
Record an explicit acuity-chart distance reference.
Eye records preserve laterality, reference axes, chart distance, calibration provenance and geometric scale. Disc-diameter units are a relative image scale, not a physical length, and cylinder sign differs from a full prescription transformation. Supplied labels and conversions do not inspect an eye, detect disease or choose care.
Record an explicit acuity-chart distance reference.
When to use this tool
Use Acuity Chart Distance Reference Label when you already have chartId, distanceWording, referenceSource and need to record an explicit acuity-chart distance reference.
How to use the tool and how it works
- Enter chartId, distanceWording, referenceSource. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read token. Use the output convention below.
Enter chartId, distanceWording, referenceSource using the field constraints below. Encode these values, in exactly that order, as a JSON array and return the serialized array as text in token. String values are preserved without trimming or external terminology lookup.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| chartId | Chart Id | Required. Text; minimum UTF-16 length 1; maximum UTF-16 length 8192. |
| distanceWording | Distance Wording | Required. Text; minimum UTF-16 length 1; maximum UTF-16 length 8192. |
| referenceSource | Reference Source | Required. Text; minimum UTF-16 length 1; maximum UTF-16 length 8192. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| token | Token | Required. Text; maximum UTF-16 length 8192. |
{
"input": {
"chartId": "CH17",
"distanceWording": "6 m",
"referenceSource": "Chart instructions"
},
"output": {
"token": "[\"CH17\",\"6 m\",\"Chart instructions\"]"
}
}Limitations and assumptions
- The result records supplied values without converting visual acuity or choosing a testing distance. Sources and asserted relationships are not independently authenticated.
- 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.
Alternative or Complementary methods
Review the original image calibration, refraction convention and chart-distance record for substantive measurements. Use complete optical or image geometry when physical scale or clinical interpretation is required; relative disc units and axis labels preserve narrower conventions.
References
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