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.

Waist radius (µm)

Second-moment beam waist radius, paired with a consistently measured far-field divergence.

Divergence (mrad)

Second-moment far-field half-angle divergence.

Wavelength (nm)

Laser wavelength.

Compute the M² beam-quality factor and beam-parameter product from waist radius, far-field half-angle divergence, and wavelength. 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]

M²

M² propagation factor (1 for a diffraction-limited Gaussian).

BPP (mm·mrad)

Beam-parameter product w0·θ.

• 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.

• Rayleigh Range Formula

  Compute the Gaussian-beam Rayleigh range and confocal parameter from waist radius and wavelength.

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  Compare far-field spot diameters of a VCSEL and an edge emitter at a given working distance from their full-angle divergences.

• Bar Smile Pointing Budget Checker

  Translate the smile (emitter curvature) of a diode bar into far-field pointing error after collimation and check it against the budget.