Spektralmaximum

Spektralmaximum is a term used in spectroscopy and optics to denote the wavelength at which a spectrum reaches its maximum value. In practice it refers to the wavelength of maximum intensity for a light source's spectral power distribution (SPD), or the maximum value of a measured spectral quantity such as absorbance in an absorption spectrum. The specific value depends on the type of spectrum and the wavelength range considered.

For an ideal blackbody, the spectral radiance peaks at a wavelength lambda_max that shifts with temperature according to Wien's displacement law: lambda_max = b / T, where b is approximately 2.8977719 × 10^-3 m K. Thus hotter bodies emit light with shorter lambda_max; for the Sun (about 5800 K), lambda_max is around 500 nm, in the green portion of the visible spectrum.

Measuring spektralmaximum involves recording the spectrum with a spectrometer or a photodetector array and locating the wavelength with the maximum response. In laboratory settings, data may be smoothed or fitted with a curve to determine lambda_max more precisely.

Spektralmaximum is important for several practical and scientific reasons. It helps specify color rendering and color temperature in lighting design, aids in interpreting the color of astronomical objects, and supports identification of chemical species via their emission or absorption features.

See also: spectral power distribution, Wien's displacement law, Planck's law, spectroscopy.