Comb Spacing Lock
Summarize gain-switched comb spacing lock error.
Description
Comb-spacing lock statistics compare measured spacings with a target.
Comb-spacing lock statistics compare measured spacings with a target. RMS is taken about the target, so it includes mean offset as well as scatter.1
Summarize gain-switched comb spacing lock error.
When to use Comb Spacing Lock
Use this tool to summarize gain-switched comb spacing lock error.
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 Comb Spacing Lock 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 measuredSpacingsHertz, targetSpacingHertz using the field table and calculation rules, then run the tool.
- Read meanSpacingHertz, meanErrorHertz, rmsErrorHertz. 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 |
|---|---|---|---|
| measuredSpacingsHertz | Measured comb spacings (Hz) | list of number | Required |
| targetSpacingHertz | Target spacing (Hz) | number; minimum: 0 | Required |
Enter nonempty finite signed spacing list and nonnegative target Hz. Return mean, signed error and RMS.
meanError=mean(spacings)−target; RMS=sqrt(Σ(spacing−target)²/n) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| meanSpacingHertz | Mean spacing (Hz) | number |
| meanErrorHertz | Mean spacing error (Hz) | number |
| rmsErrorHertz | RMS spacing error (Hz) | number; minimum: 0 |
{
"input": {
"measuredSpacingsHertz": [
99,
101
],
"targetSpacingHertz": 100
},
"output": {
"meanSpacingHertz": 100,
"meanErrorHertz": 0,
"rmsErrorHertz": 1
}
}Limitations and assumptions
No lock loop, spacing extraction, time-series drift or acceptance threshold 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 DFB Array Channel Spacing: Measure adjacent wavelength spacing and spacing nonuniformity in a DFB array. For a complementary task, use Dual-Comb Time Magnification: Calculate dual-comb asynchronous sampling period and time magnification.
References
-
Comb Spacing Lock — tool.io
Similar or alternative tools
- DFB Array Channel Spacing
Measure adjacent wavelength spacing and spacing nonuniformity in a DFB array.
- Dual-Comb Time Magnification
Calculate dual-comb asynchronous sampling period and time magnification.