spektrars

Spektrars are a hypothetical unit used to quantify the concentration of spectral energy within a defined wavelength interval. In this framework, a spektrar is a dimensionless quantity that expresses how much energy a source emits within a band relative to a reference spectrum. The term is not part of standard radiometric units and is used mainly in discussions of normalization and comparative spectral analysis.

Calculation: For a spectrum with spectral radiance L(λ) and a reference spectrum L_ref(λ), over the band λ1 to λ2, the spektrar S is defined as S = ∫λ1^λ2 L(λ) dλ / ∫λ1^λ2 L_ref(λ) dλ. A value of S = 1 indicates parity with the reference in that band; S > 1 indicates higher energy, S < 1 lower energy. Because it is a ratio, the spektrar does not depend on absolute calibration if both spectra are measured consistently.

Applications: Spektrars are used to compare spectral shapes, assess filtering effects, and illustrate relative energy distribution in simulations, demonstrations, or educational materials. They allow quick, band-limited comparisons without requiring full radiometric calibration.

Limitations: The meaning of a spektrar depends on the chosen band and the reference spectrum, making it contextual. It conveys relative rather than absolute energy and can hinder comparability across laboratories that use different standards. It should be used alongside conventional radiometric quantities for complete analysis. Related concepts include spectral power distribution and radiance normalization.