Correlated Color Temperature Calculator

CCT Formula:

\[ CCT = \frac{2.897 \times 10^6}{\lambda_{peak}} \]

Correlated Color Temperature (CCT):

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1. What is Correlated Color Temperature?

Correlated Color Temperature (CCT) is a specification of the color appearance of a light source, relating its color to the color of light from a theoretical black body radiator heated to a specific temperature. It is measured in Kelvin (K) and describes whether light appears warm (lower CCT) or cool (higher CCT).

2. How Does the Calculator Work?

The calculator uses the CCT formula:

\[ CCT = \frac{2.897 \times 10^6}{\lambda_{peak}} \]

Where:

\( CCT \) — Correlated Color Temperature (Kelvin)
\( \lambda_{peak} \) — Peak wavelength (nanometers)
\( 2.897 \times 10^6 \) — Wien's displacement constant

Explanation: This formula is derived from Wien's displacement law, which relates the peak wavelength of black body radiation to its temperature.

3. Importance of CCT Calculation

Details: CCT is crucial in lighting design, photography, display technology, and visual arts. It helps determine the color quality and appearance of light sources, affecting mood, visibility, and color rendering in various environments.

4. Using the Calculator

Tips: Enter the peak wavelength in nanometers (nm). The value must be positive and non-zero. Common peak wavelengths range from approximately 380 nm (violet) to 780 nm (red).

5. Frequently Asked Questions (FAQ)

Q1: What is the typical CCT range for different light sources?
A: Candlelight (~1500K), Incandescent bulbs (2700-3000K), Fluorescent lights (3000-6500K), Daylight (5000-6500K), Overcast sky (6500-10000K).

Q2: How does CCT affect human perception?
A: Lower CCT (warm light) creates a cozy, relaxing atmosphere, while higher CCT (cool light) promotes alertness and is better for task-oriented activities.

Q3: Is CCT the same as color rendering index (CRI)?
A: No, CCT describes the color appearance (warm/cool), while CRI measures how accurately a light source reveals the true colors of objects compared to natural light.

Q4: What are the limitations of this calculation?
A: This formula provides an approximation based on peak wavelength. For precise CCT determination of real light sources, more complex calculations considering the full spectral distribution are often required.

Q5: How is CCT used in practical applications?
A: Used in LED manufacturing, architectural lighting, photography white balance settings, display calibration, and creating specific atmospheres in interior design.