1. What is Wien's Displacement Law?

Wien's Displacement Law describes the relationship between the temperature of a black body and the wavelength at which it emits the most radiation. It's fundamental to understanding color temperature in lighting and thermal radiation.

2. How Does the Calculator Work?

The calculator uses Wien's Displacement Law:

Where:

• \( \lambda_{max} \) — Peak wavelength in nanometers (nm)
• \( T \) — Absolute temperature in Kelvin (K)
• 2.89776829 × 10⁶ — Wien's displacement constant (nm·K)

Explanation: As temperature increases, the peak wavelength decreases, shifting toward the blue end of the spectrum.

3. Importance of Color Temperature

Details: Color temperature is crucial in lighting design, photography, astronomy, and thermal imaging. It helps characterize the quality of light sources and understand thermal radiation properties.

4. Using the Calculator

Tips: Enter the temperature in Kelvin (must be > 0). The calculator will determine the wavelength of peak emission in nanometers.

5. Frequently Asked Questions (FAQ)

Q1: What is a black body in physics?
A: A black body is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence.

Q2: How does this relate to visible light?
A: For temperatures around 5000-6500K, peak emission is in the visible spectrum (sunlight). Lower temperatures peak in infrared, higher in ultraviolet.

Q3: What's the color temperature of daylight?
A: Daylight typically ranges from 5000K (cool white) to 6500K (daylight white), with the sun at about 5778K.

Q4: Can this be used for non-blackbody sources?
A: The calculation is strictly for ideal black bodies. Real light sources may have different spectral distributions.

Q5: What's the significance of the 1931 CIE standard?
A: The 1931 CIE color space established the first quantitative link between physical wavelengths and human color perception.