Holography Fringe Stability

Compare measured holography path drift with a caller-supplied wavelength-fraction requirement.

Description

Holography drift screening expresses allowed path variation as a supplied fraction of wavelength.

Holography drift screening expresses allowed path variation as a supplied fraction of wavelength. Comparison uses the measured absolute drift.^[1]

Compare measured holography path drift with a caller-supplied wavelength-fraction requirement.

When to use Holography Fringe Stability

Use this tool to compare measured holography path drift with a caller-supplied wavelength-fraction requirement.

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 Holography Fringe Stability 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 wavelengthMeters, measuredPathDriftMeters, allowedWavelengthFraction using the field table and calculation rules, then run the tool.
Read allowedPathDriftMeters, stabilityMarginMeters, withinRequirement. 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
wavelengthMeters	Wavelength (m)	number; minimum: 0	Required
measuredPathDriftMeters	Measured path drift (m)	number; minimum: 0	Required
allowedWavelengthFraction	Allowed wavelength fraction	number; minimum: 0	Required

Enter nonnegative wavelength, drift and allowed fraction. Return allowed meters, signed margin and inclusive gate.

allowed=λ×fraction; margin=allowed−drift

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
allowedPathDriftMeters	Allowed path drift (m)	number; minimum: 0
stabilityMarginMeters	Path-stability margin (m)	number
withinRequirement	Within requirement	boolean

json

{
  "input": {
    "wavelengthMeters": 5e-7,
    "measuredPathDriftMeters": 1e-7,
    "allowedWavelengthFraction": 0.25
  },
  "output": {
    "allowedPathDriftMeters": 1.25e-7,
    "stabilityMarginMeters": 2.5e-8,
    "withinRequirement": true
  }
}

Limitations and assumptions

No fixed fringe-stability criterion, phase noise or exposure-time averaging is supplied.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. 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 Interferometer Displacement: Convert reflected-path fringe count to displacement with refractive-index and angle correction. For a complementary task, use Maréchal Strehl: Estimate Strehl ratio from RMS wavefront error with the Maréchal relation.

References

Holography Fringe Stability — tool.io

Similar or alternative tools

Interferometer Displacement
Convert reflected-path fringe count to displacement with refractive-index and angle correction.
Maréchal Strehl
Estimate Strehl ratio from RMS wavefront error with the Maréchal relation.