LEDs - How Bright Are They?
August 2012 Newsletter
The whole field of LED lighting is a minefield for the exhibition and display designer. The lower energy use and reduction in heat output make LED’s an ideal step forward for our industry; but the inconsistency in light quality and output per watt and the obfuscation from many manufacturers can make planning an installation into a “best guess” exercise, and none of us wants that.
Here at Aardvark Lighting we are supplying more and more LED lighting solutions, from retro-fitting LED 12v or GU10 bulbs, through to LED flexible strip to LED light boxes. The question we are always asked, and which we ask ourselves is “how bright is it?”
To try to answer this question we have had to go back to basics. For years we have grown accustomed to equating wattage to light output – a 50 watt spotlight, a 200 watt floodlight etc. and in the end, this will probably be a good approximation for LED’s, but at present this can be very misleading. The problem occurs because of the massive variations in the basic Light Emitting Diode from one manufacturer to another. The technology is still taking massive technical steps forward in terms of light output per watt. In our workshop we have some 5watt GU10’s which are virtually twice as bright (light output) as a 4 watt GU10. The difference is in the inner workings of the LED itself, not in the bulb design or wattage. As designers, what we need to focus on is the light output for each bulb or light source. The light output is measured in Lumens (lm) on a linear scale (ie 2 lumens are twice as bright as one lumen)
For our own internal use we have developed a fairly crude table of light outputs so that we can better answer the question: “How bright are they” and you may find this helpful in designing your next exhibition.
Bulb |
Light Output |
Halogen Spotlight Equivalent |
“Traditional” MR16 or GU10 50W halogen spotlight |
750 lm |
|
“Traditional” Linear Halogen 160 W floodlight |
3,100 lm |
|
3W LED GU10 Bulb |
150 lm |
10 watt |
4W LED GU10 Bulb |
175 lm |
12 watt |
5W LED GU10 Bulb |
390 lm |
26 watt |
9W LED 12v Downlight |
650 lm |
43 watt |
4w per metre LED Flexible Strips |
60 lm |
4 watt |
14W per metre LED Flexible Strips |
900 lm |
60 watt |
20W per metre LED Flexible Strips |
1020 lm |
68 watt |
A1 size Lightbox |
1600 lm |
107 watt |
600mm square Lightbox |
3302 lm |
220 watt |
This isn’t the whole story though, because there is also light quality. The above table is for Daylight or White Light bulbs. There also warm white options which will reduce the lumen output per watt, sometimes dramatically.
If you want to use LEDs and want help and advice in planning your lighting, why not give us a call and we can help you from our most up-to-date information, which currently changes almost weekly. Call our technical team on 01709 300050 or email your query to aardvarklighting@live.co.uk
We look forward to your query
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Tags: led. led lighting. how bright are leds led comparison led lighting solutions led flexible strip led lightbox led light box led gu10 led 12v led low voltage.