Which LEDs are good in daylight?

William At MyBlueRoom

New Member

• May 6, 2006

• #1

Which LEDs are good in daylight?
For an electronic LED sign.

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• May 7, 2006

• #2

William At MyBlueRoom said:

Which LEDs are good in daylight?
For an electronic LED sign.

Click to expand...

Bright ones!

 

lord loh.

Member

• May 7, 2006

• #3

Red LEDs have the least disperssion...

Great Joke Nigel... 5 stars for it from me....

 

justDIY

Active Member

• May 7, 2006

• #4

go with yellow-green or just green

those colors lie in the peak sensitivity region for human vision, although if you want something to be noticed, blue is very eye catching, even though it is one of the colors our eyes are least sensitive to.

 

zachtheterrible

Active Member

• May 7, 2006

• #5

Along the lines of nigel's comment, bright ones, the 1W LEDs from lumiled are incredibly bright and will catch attention. Unless there's gonna be a lot of them then the $2.00-$3.00 price tag might get expensive depending on how many you are using. If I were you, I would use the 1W emitter, rather than getting the 1W star, as they cost around an extra dollar for the heatsink. You could mount the emitters to aluminum and save some money. Of course you'll have to decide for yourself. Just don't run the emitter at full power without a heatsink, it'll burn up.

check 'em out at lumileds.com

 

Someone Electro

New Member

• May 7, 2006

• #6

Yea those should be quite visuble.

In trafic they put leds in to holes.This reduces wiwing angle but also prevens sun iluminating them.They use superbright orange,white and yelow leds

Oh and nice avatar zach hehe

 

akg

New Member

• May 7, 2006

• #7

white leds (costly?)

 

Someone Electro

New Member

• May 8, 2006

• #8

Yea white leds are prety expensive they cost about the same as blue ones.Its aculy s blue led whith a phosphor coat.

 

Dr.EM

New Member

• May 8, 2006

• #9

These may work, though they have a small viewing angle:

**broken link removed**

 

justDIY

Active Member

• May 8, 2006

• #10

some more options to consider:

1) specifically built for outdoor signs:
**broken link removed**

2) amber aka DOT yellow (super frickin cheap):
**broken link removed**

 

William At MyBlueRoom

New Member

• May 8, 2006

• #11

Those 10c DOT yellow look great, but 1000hrs operating life? Isn't that short for an LED?

 

Someone Electro

New Member

• May 8, 2006

• #12

You might try looking here **broken link removed**
if you need a lot of leds cheap.They have anything from a standard 5mm led to a luxeon.

 

justDIY

Active Member

• May 9, 2006

• #13

William At MyBlueRoom said:

Those 10c DOT yellow look great, but 1000hrs operating life? Isn't that short for an LED?

Click to expand...

where did you see 1000hr operating life? depending on your thermal design, I'd expect these LEDs to operate at least 25000 hrs, if not more. Also you have to consider being outdoors, the junction will be exposed to strong UV radiation (unless you provide some sort of filter) - this eventually will ruin them as well.

oh, i see where you found the 1000 hr, that is under test data - they performed certain tests for a duration of 1000 hrs.