Use this laser calculation or lookup for a first-pass optics, pulse, beam, gain-medium, diode, fiber, or safety comparison under explicitly stated wavelength and operating conditions.

n_eff

Effective refractive index of the lasing mode.

Bragg wavelength (nm)

Target first-order Bragg wavelength.

Order

Diffraction order of the grating coupling.

Compute the DFB grating pitch that satisfies the Bragg condition for a target wavelength and effective index. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Grating period (nm)

Required grating pitch.

• Laser behavior depends on wavelength, mode, coherence, pulse shape, beam quality, cavity and optical losses, material data, temperature, alignment, nonlinear effects, damage thresholds, and measurement definitions. Lookup values are not substitutes for current device data or laser-safety analysis.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Verify constants and limits with primary literature and manufacturer data, propagate tolerances, model the complete optical train, and apply the relevant laser safety standard.

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