An isocandela line is a graphical representation of the light intensity (candela) in different directions around a light source or fixture. It is used in lighting engineering and design to analyze the distribution and intensity of light .
1. How does an Isocandela line work?
An isocandela diagram shows lines of equal light intensity around a light source. These lines connect points with the same candela value and provide insight into the light distribution.
📌 Key Features:
🔹 Indicates the light distribution of a lamp or fixture in a specific plane.
🔹 Shows light distribution in candela (cd) → The brighter an area, the higher the candela value.
🔹 Used in polar diagrams → Visualizes how light spreads horizontally and vertically.
🔹 Helps with the selection and placement of luminaires in a lighting plan.
💡 Example: A spotlight has narrow isocandela lines , while a floodlight has wide lines that show a greater light spread.
2. Applications of Isocandela lines
| Application | Why is an Isocandela line important? |
|---|---|
| 💡 Street lighting | Optimize light distribution and reduce glare. |
| 🏢 Architectural lighting | Determining the right luminaires for facades and interior spaces. |
| 🎭 Theater and stage lighting | Precision in directing light beams. |
| 🚗 Car lighting | Designing headlights with the right light distribution. |
| 📷 Photography & film lighting | Checking shadows and highlights in image lighting. |
📌 Isocandela diagrams are often used by lighting designers and engineers for precise lighting studies.
3. Difference between Isocandela lines and Iso-lux lines
| Feature | Isocandela lines | Iso-lux lines |
|---|---|---|
| Unit | Candela (CD) | Lux (lx) |
| Measured value | Light intensity in a certain direction | Illuminance on a surface |
| Display | Polar diagram | Plane diagram (2D) |
| Application | Light beam and distribution | Light intensity on floor, walls or work surface |
📌 Isocandela lines measure light intensity in the air, while isolux lines measure how light strikes a surface.
💡 In short:
An isocandela line is a graphical representation of light intensity (candela) in different directions , used in lighting design, street lighting, architecture, and automotive lighting . It helps optimize light distribution and prevents unwanted glare .