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Wavelength · Frequency · Wavenumber · EnergyFour Coordinates of Light

Four ways to describe the same light — edit any field and the other three update instantly.

Converter
Common: 760.8 (O₂) 980 (pump) 1310 1550 1653.7 (CH₄)
ν = c / λ wavenumber = 10⁷ / λ(nm) E(eV) = 1239.84 / λ(nm) c = 299,792,458 m/s (exact)

Each coordinate has its home field

Wavelength is the common language of datasheets. Frequency rules coherent communications and DWDM — the ITU grid is anchored at 193.1 THz (≈1552.52 nm) with 50/100 GHz spacing, and laser frequency stability is quoted in MHz/GHz. Wavenumber (cm⁻¹) is the standard of spectroscopy and TDLAS literature — HITRAN line positions are listed in wavenumbers. Photon energy decides whether a detector can "see" the light at all: it must exceed the material bandgap — InGaAs at ≈0.73 eV cuts off near 1.7 µm, which is exactly why InGaAs detectors serve the 1310/1550 nm bands.

Check value: 1550 nm = 193.414 THz = 6451.61 cm⁻¹ = 0.7999 eV.

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※ Formulas on this page assume ideal models; all device parameters shown are typical values — refer to the datasheet and the serialized factory test report shipped with each unit. For selection support, contact sales@lncetek.com.