ECN Forum Forums Technical Discussion Electrical Theory and Applications Luminous Flux?

Can anyone explain to me, the meaning of the term Luminous Flux.
I realise that this term relates to Lighting, but how is this term used practically?.
Cheers,
Mike.

Hello Mike!

I will take a stab at this one for you.

Luminous Flux:

Expressed in Lumens, it is the time rate of the flow of Light.

Radiant energy in the visible region of the spectrum, varies in its ability to produce visual sensation; the variation depending on the wavelength.

Simply, some colors appear "brighter" than others.

The ratio of the luminous flux to the corresponding radiant flux is the Luminosity Factor, or Visibility Factor - and is expressed in Lumens Per Watt.
This varies with wavelength, having a maximum at approximately 5,550 Angstroms.

In a nutshell, the topic is referring to the color tones which comprise White Light - either as individual, stand-alone colors, as "mixed" combinations of colors, or all colors combined - as in White Light.

Sound kind of right? Also, does this make sense and/or appear to be what you are looking for as a description?

Scott35

Yes Scott, that explained it perfectly mate!.
I haven't heard the Angstrom used in a few years.
But I remember it being used when I was an Apprentice Liney, we were talking about Street-Lighting and the lack of colour-rendering that Sodium Lighting has.
Is the CRI used in the US?.

Glad to help!

Yes, CRI is a commonly used reference for discharge Lamps here in the U.S.
Best CRI is with Metal Halide Lamps.

Scott35