sci.spectral-radiance-Planck-blackbody Calculator
Calculates Planck spectral radiance B_λ = 2hc²/λ⁵ / (exp(hc/λkT) − 1) and Wien's displacement law peak wavelength λ_max = 2898/T µm. At T = 5,778 K (Sun): λ_max = 501 nm (green) — at T = 300 K (room temperature): λ_max = 9.7 µm (far infrared, used in thermal imaging cameras).
Inputs
- Lambda Nm
- Distance between successive wave crests. Related to frequency: λ = speed / frequency.
- T K
- Thermal state of the substance. Check whether the formula needs Celsius, Fahrenheit, or Kelvin (K = °C + 273.15).
Results
- spectral radiance B_λ (W/sr/m²/nm)
- Sample size or count used in the calculation.
- peak wavelength λ_max (nm) — Wien
- The computed linear length.
- total radiated power (W/m²) — Stefan-Boltzmann
- The combined total across all inputs and components.
- B_λ = 2hc²/λ⁵ · 1/(e^(hc/λkT)−1)
- Reference formula or conversion factor shown for context.
- colour temperature
- Colour temperature in Kelvin -- describes the warmth or coolness of light. 2700K: warm white (incandescent). 4000K: neutral white. 6500K: daylight.
- energy density
- Sample size or count used in the calculation.
peak blackbody radiance spectral wavelength