Eye-Clean Threshold Size
Compare already apparent inclusion width to caller visual angular-resolution model; real contrast, lighting, depth/refraction and observer acuity remain unmodeled, so this is not an eye-clean certification.
Description
Apparent inclusion width subtends an angle at the observer.
Apparent inclusion width subtends an angle at the observer. A declared angular-resolution threshold is a simplified geometric visibility proxy.1
Compare already apparent inclusion width to caller visual angular-resolution model; real contrast, lighting, depth/refraction and observer acuity remain unmodeled, so this is not an eye-clean certification.
When to use Eye-Clean Threshold Size
Use this tool to compare already apparent inclusion width to caller visual angular-resolution model; real contrast, lighting, depth/refraction and observer acuity remain unmodeled, so this is not an eye-clean certification.
Prepare the gemstone measurements, spectra or comparison data and any supplied calibration parameters. Check units, reference conditions and record alignment.
How to use Eye-Clean Threshold Size and understand its results
- Prepare the gemstone measurements, spectra or comparison data and any supplied calibration parameters. Check units, reference conditions and record alignment.
- Enter apparentInclusionWidthMm, viewingDistanceMm, callerAngularResolutionArcminutes using the field table and calculation rules, then run the tool.
- Read apparentInclusionAngularWidthArcminutes, callerResolutionWidthThresholdMm, aboveCallerAngularResolution. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| apparentInclusionWidthMm | Apparent inclusion width mm | number | Required |
| viewingDistanceMm | Viewing distance mm | number | Required |
| callerAngularResolutionArcminutes | Caller angular resolution arcminutes | number | Required |
Use positive viewing distance in mm, nonnegative apparent width and angular resolution in (0,10,800) arcminutes. Convert angular width to arcminutes and return the equivalent width threshold and a strict above-resolution flag.
angular width=2atan(width/(2distance)); threshold width=2distance tan(resolution angle/2) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| apparentInclusionAngularWidthArcminutes | Apparent inclusion angular width arcminutes | number |
| callerResolutionWidthThresholdMm | Caller resolution width threshold mm | number |
| aboveCallerAngularResolution | Above caller angular resolution | boolean |
{
"input": {
"apparentInclusionWidthMm": 0.1,
"viewingDistanceMm": 300,
"callerAngularResolutionArcminutes": 1
},
"output": {
"apparentInclusionAngularWidthArcminutes": 1.1459155796513172,
"callerResolutionWidthThresholdMm": 0.08726646321506103,
"aboveCallerAngularResolution": true
}
}Limitations and assumptions
Contrast, lighting, refraction, depth and individual acuity are omitted. The flag is not eye-clean certification.
Numeric inputs and returned numeric values must be finite; an unrepresentable returned value produces an error. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Facet Polish Line Visibility Rater: Audit measured polish-line contrast and instrument-resolvable width simultaneously under caller thresholds; not spatial RMS contrast or universal observer/commercial polish grade. For a complementary task, use Clarity Inclusion Position Map Code: Encode measured inclusion locations into caller radial/depth zones under explicit centered circular envelope; no clarity grade, inclusion composition or visibility/structural-safety conclusion.
References
-
Eye-Clean Threshold Size — tool.io
Similar or alternative tools
- Facet Polish Line Visibility Rater
Audit measured polish-line contrast and instrument-resolvable width simultaneously under caller thresholds; not spatial RMS contrast or universal observer/commercial polish grade.
- Clarity Inclusion Position Map Code
Encode measured inclusion locations into caller radial/depth zones under explicit centered circular envelope; no clarity grade, inclusion composition or visibility/structural-safety conclusion.