lumen to lux and back

Questions and answers on how to convert things from one unit or system to another


lumen to lux and back

Postby Jimmyjazz » Fri Jan 12, 2007 4:51 pm

I know lux is lumens hitting a square metre, so you can't directly convert them.
I'm shopping for light therapy devices, and half the time they are described in lux and half the time in lumens. I don't know why they would use lux as eyeballs aren't square metres in size.
I've read using a 10,000 lux light source for 30 mins is recommended. I have light bulbs that are 700 lumens and 1740 lumens. Can someone please help with converting this?

and I don't understand how they can say 10,000 lux without giving a distance. is that square metre next to the light or a room away? argh

Would it make sense to day that the pupils combine to about a cm squared, so 1/10000th of the # of luxes is how many lumens get in your eyes?
Posts: 1
Joined: Fri Jan 12, 2007 4:42 pm

lumens and lux

Postby ergognome » Thu Mar 06, 2008 8:33 pm

I realize that the original post was over a year ago but my answer may help with part of the question. Lux are useful because they describe the amount of light falling on an area, [b]at that area[/b]. So if I, as an ergonomist, want to check that a desk has enough light to read documents I will measure the light at the desk with a lux-meter. Knowing the light intensity at the source is only partly helpful, as the useful light is dependent upon the distance you are away from the source.

Return to How to convert?

Who is online

Users browsing this forum: No registered users and 4 guests

Our Privacy Policy       Cooking Measures Converter       Metric conversions