Technical meaning
- Luminous intensity describes light output in a given direction.
- It differs from luminous flux because it depends on where the light is aimed or distributed.
Calculation use
- Simple beam and room estimates usually work from lumens, area and beam angle, while intensity data belongs to more detailed optical notes.
- Intensity helps explain why narrow beams can produce strong highlights or eye-level brightness.
Not the same as
- Luminous intensity is not the same as total lumen output.
- It is not a complete glare assessment without observer position, background brightness and luminaire data.
Australian context
- Australian outdoor, retail and workplace lighting notes should keep directional brightness distinct from total output and maintained illuminance.
Examples
| Example | Value | Planning note |
|---|
| Spotlight beam | directional output | Useful for highlighting but sensitive to aiming. |
|---|
| Floodlight beam | broader distribution | Can still cause glare if aimed toward a viewer. |
|---|
| Photometric data | intensity by angle | Needed for more detailed optical checks. |
|---|
Calculation limits and records
- This term supports optical understanding. It does not replace luminaire photometry or project-specific glare review.