Lighting study #4 (inverse lighting design)

Original empirical lighting design with 10 rectangular flat panel luminaires.

This solution does not take into account the geometry and properties of materials.
It was probably found by empirical methods (room cavity or similar).
The image also shows other luminaires used for task lighting.

A lighting design solution with 6 spotlight 120 degrees luminaires.

This solution was found by optimisation and the luminaires were optimsed with the following goals:

luminaires near the ceiling
luminaires directed to the floor
luminaires in row
maximise lighting in the desk tops
minimise lighting (glare) in user face (sitting position)

This solution has some drawbacks due to the small size and directionality of the luminaires.
It creates sharp umbra and penumbra transitions around the desk top.

A lighting design solution with 6 omni-direcional luminaires.

This solution was found by optimisation and the luminaires were optimised with the same goals as in above case.
This solution also has drawbacks due to the small size of the luminaires.
There are also sharp umbra and penumbra transitions around the desk top.

A lighting design solution with 5 rectangular flat panel luminaires.

This solution was found by optimisation and the luminaires were optimised with the following goals:

luminaires in the ceiling
luminaires in row
spacing between pairs of luminaires restricted to a predefined range
maximise lighting in the desk tops
minimise lighting (glare) in user face (sitting position)

This is the best solution.
It avoids disturbing umbra and penumbra transitions and ambient lighting still seems adequate.

Last change: 31 March 1998

António Costa