What is beam angle in LED calculations?

Beam angle is the angle between the directions in which the luminous intensity is 50% of the maximum. It determines how the light is distributed and affects the conversion from lumens to candela.

Lumen to mcd Calculator

Q: How do you convert lumens to millicandela?

To convert lumens to millicandela, use the formula: mcd = (lumens × 1000) ÷ (2π × (1 - cos(θ/2))), where θ is the beam angle. This converts luminous flux to luminous intensity.

Q: What is the difference between lumens and millicandela?

Lumens measure total luminous flux (total light output), while millicandela measures luminous intensity (light intensity in a specific direction). One candela equals 1000 millicandela.

Convert lumens to millicandela (mcd) with step-by-step calculations. Perfect for LED specifications, lighting design, and photometric calculations.

Luminous Flux to Luminous Intensity Converter

Lumens (lm):

Beam Angle (degrees):

10° (Spot) 30° (Narrow) 60° (Medium) 120° (Wide)

Common Lumen to mcd Conversions

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Understanding Lumen to Millicandela Conversion

Converting lumens to millicandela involves transforming total luminous flux to luminous intensity in a specific direction. This conversion is essential for LED specifications and lighting calculations.

Conversion Formula

mcd = (lumens × 1000) ÷ (2π × (1 - cos(θ/2)))

Where:
• mcd = millicandela (luminous intensity)
• lumens = luminous flux
• θ = beam angle in degrees
• π = 3.14159...

Key Concepts

Lumens (lm): Total luminous flux - the total amount of visible light emitted
Millicandela (mcd): Luminous intensity - light intensity in a specific direction (1 cd = 1000 mcd)
Beam Angle: The angle between directions where intensity is 50% of maximum
Solid Angle: The three-dimensional angle subtended by the light beam

Applications

Application	Typical Beam Angle	Use Case
LED Spotlights	10-30°	Accent lighting, task lighting
LED Floodlights	60-120°	Area lighting, general illumination
LED Indicators	15-45°	Status lights, displays
Automotive LEDs	varies	Headlights, turn signals
Display Backlighting	120-180°	LCD/OLED backlights

Frequently Asked Questions

How do you convert lumens to millicandela?

Use the formula: mcd = (lumens × 1000) ÷ (2π × (1 - cos(θ/2))), where θ is the beam angle. This converts total luminous flux to luminous intensity in a specific direction.

What is the difference between lumens and millicandela?

Lumens measure total light output (luminous flux), while millicandela measures light intensity in a specific direction. The conversion depends on how the light is distributed (beam angle).

Why is beam angle important in this conversion?

Beam angle determines how concentrated the light is. A narrower beam angle results in higher luminous intensity (mcd) for the same total light output (lumens).