Visible-band fraction of thermal emission
An incandescent source cannot put more of its radiated power into visible light than the Planck spectrum at its temperature contains there; the ceiling rises with temperature towards the ≈ 6600 K blackbody optimum and is a few per cent at filament temperatures. The band integral has no closed form, so the check records the bound as not evaluable until a band-fraction table or series is curated; a datum compared with it must state the emitter temperature.
Atlas record: 1 claim references this constraint — 1 established.
Explorerelations · sources · cite
η_vis ≤ ∫₃₈₀ⁿᵐ⁷⁸⁰ⁿᵐ B_λ(λ, T) dλ / σT⁴ — the share of a thermal emitter's radiated power that Planck's distribution places in the visible band at the emitter temperature
Relations
- visible light delivered by a thermal emitter at temperature T; the bound is the Planck band fraction at that T
Cited sources · 1
- [1]A. Bejan. Advanced Engineering Thermodynamics (4th ed.) (2016)
Cite this entity
Physical Transformation Atlas (2026). entity constraint:planck-visible-band-fraction: Visible-band fraction of thermal emission. Dataset revision rbfbfcbb70e57 (hash of the canonical data). https://physical-transformation-atlas.wldud5192.workers.dev/e/constraint/planck-visible-band-fraction
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