1. What is Luminous Flux?

Definition: Luminous flux measures the total quantity of visible light emitted by a source per unit time.

Purpose: This calculator helps determine the total luminous flux based on light intensity and illuminated area.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Φ \) — Luminous flux (lumens)
• \( I \) — Light intensity (lumens/m² or lux)
• \( A \) — Illuminated area (m²)

Explanation: The total luminous flux is calculated by multiplying the light intensity by the area it illuminates.

3. Importance of Luminous Flux Calculation

Details: Proper calculation ensures adequate lighting for spaces, energy efficiency, and compliance with lighting standards.

4. Using the Calculator

Tips: Enter the light intensity in lumens/m² (lux) and the illuminated area in square meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between luminous flux and illuminance?
A: Luminous flux (Φ) is total light output, while illuminance (lux) is flux per unit area (lumens/m²).

Q2: How does area affect luminous flux?
A: For a given light source, increasing area decreases illuminance (lux) but total luminous flux remains constant.

Q3: What's a typical luminous flux for household bulbs?
A: Standard 60W incandescent: ~800 lumens, 100W: ~1600 lumens, LED equivalents use less power for same flux.

Q4: When would I need this calculation?
A: When designing lighting systems, comparing light sources, or verifying lighting requirements for spaces.

Q5: How does distance affect these calculations?
A: Light intensity follows inverse-square law with distance, but this calculator assumes uniform intensity over the area.