Diode Filamentation Index
Quantify broad-area diode filamentation from near-field intensity samples.
Description
Near-field hotspot screening compares each intensity with a multiple of the mean.
Near-field hotspot screening compares each intensity with a multiple of the mean. A peak-to-mean ratio summarizes spatial nonuniformity.1
Quantify broad-area diode filamentation from near-field intensity samples.
When to use Diode Filamentation Index
Use this tool to quantify broad-area diode filamentation from near-field intensity samples.
Prepare the optical measurements, geometry, fitted coefficients or caller-selected thresholds requested. Confirm wavelength, radius/diameter, pulse-width, angle and unit conventions before running the calculation.
How to use Diode Filamentation Index and understand its results
- Prepare the optical measurements, geometry, fitted coefficients or caller-selected thresholds requested. Confirm wavelength, radius/diameter, pulse-width, angle and unit conventions before running the calculation.
- Enter nearFieldIntensities, hotspotMultiple using the field table and calculation rules, then run the tool.
- Read meanIntensity, filamentationIndex, hotspotCount. 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 |
|---|---|---|---|
| nearFieldIntensities | Near-field intensity samples | list of number | Required |
| hotspotMultiple | Hotspot threshold multiple | number; minimum: 0 | Required |
Enter nonempty nonnegative intensities with positive mean and nonnegative multiple. Return mean, index and inclusive hotspot count.
index=max(intensities)/mean; hotspots=count(value≥mean×multiple) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| meanIntensity | Mean intensity | number; minimum: 0 |
| filamentationIndex | Peak-to-mean intensity | number; minimum: 0 |
| hotspotCount | Hotspot count | integer; minimum: 0 |
{
"input": {
"nearFieldIntensities": [
1,
1,
4
],
"hotspotMultiple": 2
},
"output": {
"meanIntensity": 2,
"filamentationIndex": 2,
"hotspotCount": 1
}
}Limitations and assumptions
No spatial coordinates, smoothing, filament width or physical instability diagnosis is supplied.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Speckle Contrast: Calculate population speckle contrast from an intensity region. For a complementary task, use PCSEL Aperture Intensity: Calculate PCSEL aperture area and average output intensity.
References
-
Diode Filamentation Index — tool.io
Similar or alternative tools
- Speckle Contrast
Calculate population speckle contrast from an intensity region.
- PCSEL Aperture Intensity
Calculate PCSEL aperture area and average output intensity.