Millicandela = --





A Lumens to Millicandela Calculator is a helpful tool for converting the total light output of a source (lumens) to its intensity in a specific direction (millicandela). This is especially useful for focused light sources like LEDs.

What Are Lumens and Millicandela?

  • Lumens (lm) measure the total light emitted by a source in all directions. It represents the overall brightness.
  • Millicandela (mcd) measure the intensity of light in a specific direction.

The two units are related, but the conversion depends on the beam angle of the light source. A narrow beam concentrates light, resulting in a higher intensity in millicandela.

The Conversion Formula

To convert lumens to millicandela, you need the beam angle of the light source. The formula is:
Millicandela = (Lumens × 1000) ÷ Beam Angle Factor

The Beam Angle Factor is calculated as:
Beam Angle Factor = 2 × π × (1 − cos(θ/2))
Where θ is the beam angle in degrees.

Simplified Example

For an LED with:

  • 50 lumens output
  • A beam angle of 30°
  1. Calculate Beam Angle Factor:
    Beam Angle Factor ≈ 0.079 (for 30°)
  2. Millicandela = (50 × 1000) ÷ 0.079 ≈ 632,911 mcd

Why Use a Lumens to Millicandela Calculator?

  1. Accuracy: Automates complex calculations, ensuring precision.
  2. Lighting Design: Helps in selecting focused light sources for specific applications like flashlights or spotlights.
  3. Ease of Use: Quickly converts between units without manual computation.

Applications of Lumens to Millicandela Conversion

  • LED Design: Compare LEDs with different beam angles and intensities.
  • Flashlight Performance: Determine the directional brightness of a flashlight.
  • Display Technology: Optimize light intensity for screens or indicator lights.

Conclusion

A Lumens to Millicandela Calculator simplifies the process of converting total light output to directional intensity. It’s an invaluable tool for engineers, designers, and hobbyists who work with LEDs and focused lighting systems.