The effective wavelength for broadband fringe detection using fringe scanning
نویسنده
چکیده
The spectroscopic wavenumber is a proxy for the optical frequency, and avoids the necessity of writing factors of c everywhere. For optical and infrared radiation the wavenumber is conveniently expressed in units of inverse micrometers, thus a wavelength of 500 nm corresponds to 2.00 μm−1. The circular or angular wavenumber k = 2π/λ = 2πσ is often used, particularly in the context of the wave equation. Like the “ordinary” frequency (f or ν) and the circular frequency ω it is easy to confuse the two kinds of wavenumber!
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