color LED?

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mercrazy
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color LED?

i need 2 different color LEDs.
what is the highest lumen LED in red or green? these are not 2 colors in 1 LED but 2 separate LEDs.
will 100 lumens of red appear the same brightness as 100 lumens of green?
thanks

mercrazy

Enderman
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10k+ lumens of green:
https://www.osram-os.com/osram_os/en/products/product-catalog/led-light-...
A few hundred lumens of red:
https://www.osram-os.com/osram_os/en/products/product-catalog/led-light-...
100lm of any colour should look about the same brightness, the problem is finding red LED that can output as many lumens as a green LED.

Lexel
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LE R Q8WP seems like a nice LED with XPL footprint

just stupid you have to order 2000 of those

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mercrazy
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wow, that green is unbelievable.
looks like red is the hard one. i guess i’ll get the brightest red and pick greens to match lumens.
where can i buy samples of those reds?
any idea on price?
thanks

mercrazy

Vegas LED Fan
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If you really want to do it the budget way, order some COBs from China for less than a dollar. The design of these chips is with white being 100 lumens so red ends up being 80 lumens since red LEDs give off less light than the comparable white ones. I’m not sure of green though. It says 80-100 lumens per COB. They are rated for 12V DC. Three amber ones made a really nice turn signal for my car. An alternative is to buy a bulb for a car. I tried that with red and was pleased with how bright they were. I didn’t end up using them for the stop light in the car but since they cost so little, it was worth the experiment.

The COBs go by the name “7 Color COB Chip” or “7 Color Boat COB”

If you cut and paste the followingbold numbers into the Ebay search box you will see examples at the prices I listed
Bare chip (waterproof) $.78 282529971555
Encased in a plastic module $.98 302416489818
Higher power COB chips from 10 to 100W but these need a heat sink to keep from frying $.85 to $2.34 depending on wattage 252992793984
Auto bulb with a T10 base, 100 lumen 12 LED $.99 112574579558

DoubleA
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red is always dimmer when compared to green of the same wattage. Smile

Then there is the wave length issue which decides what color can be seen from the farthest.

and on the first day he said "Let there be light"...

MorePower
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Phlatlight PT54 has a high output red LED.

https://www.ebay.com/itm/Phlatlight-PT-54-Red-625nm-700-Lumen-LED-With-H...
Or buy it directly from DTR-LPF’s webstore instead of ebay: https://sites.google.com/site/dtrlpf/home/led-s

alpg88
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the way our eye sees it, depends a lot on wavelength, red will always be dimmer to our eyes than green, even if sphere sees same lumen number,

if you looking for bright red or green, cree has nothing to offer, xpe2 are about 100-150lm tops for colors. you need either luminus sst leds, or ledengin lz4.

Enderman
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Vegas LED Fan wrote:
white being 100 lumens so red ends up being 80 lumens since red LEDs give off less light than the comparable white ones.

Uh, if white is 100lm then red would be more like 10-20…
I don’t think you realize how much less lumen output you get on the red spectrum.
Vegas LED Fan
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It is true that red LEDs have a much lower output compared to natural white. As best I can figure out from the listings for COBs shown above it is around 400 lumens for red and 900 lumens for cool white if the table at this eBay listing is correct 131747229566. They list Green as 700 lumnes. It is complicated by the human eye seeing colors differently. Some sellers list “luminous intensity” as a way to compare lights of different colors rather than just lumens.

I own both a XML-T6 red and a XML-T6 white flashlight. The red one was rated 800 lumens which agrees perfectly with the CREE spec sheet for the output at 1500 mA. The white one is around 1000 lumens and I have seen the spec sheet for white listing it from 980 to 1070 lumens for the T-6 bin. Both are really bright. You don’t want to look directly at either one.

I DIY’d one of the red 1W, 3V boat shaped COBs into a rear bike light powered by a 18650 battery and with a flasher for strobe. It is plenty bright enough to be seen during the daytime.

Enderman
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The reason red lumens are so low is because of the way the eye sees colours differently.
An integrating sphere measures the lumens with a luxmeter, and a luxmeter is calibrated to show the intensity the way the human eye sees it.
So for 1W of red vs 1W of green, the green will have a much higher reading, because that is how it would look to your eyes.

Basically, you can think of a luxmeter as an artificial eye, and that’s why red colours have far fewer lumens.

DoubleA
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you mean fewer luminous intensity? like this chart here shows about 5mm leds.

and on the first day he said "Let there be light"...

Enderman
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DoubleA wrote:
you mean fewer luminous intensity? like this chart here shows about 5mm leds.

Yes, lumens = luminous intensity = luminous flux.
DoubleA
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Enderman wrote:
Yes, lumens = luminous intensity = luminous flux.
Facepalm . lumen is a measurement of luminous flux, or the total amount of light produced by a light source whereas luminous intensity(candela) tells you how bright the light source is, which shows how far away from an object you can be and while still being able to see it?

Example a laser pointer will have an extremely low lumen value but a very high candela rating.
lumens = luminous flux luminous intensity

Update:
A good way to remember the differences between terms is:

Lumens are how much light is given off
Lux is how bright your surface will be
Candela measures the visible intensity from the light source.

and on the first day he said "Let there be light"...

Sirius9
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MorePower wrote:
Phlatlight PT54 has a high output red LED.

https://www.ebay.com/itm/Phlatlight-PT-54-Red-625nm-700-Lumen-LED-With-H...
Or buy it directly from DTR-LPF’s webstore instead of ebay: https://sites.google.com/site/dtrlpf/home/led-s


This are awesome, I have several, bought from DTR, they rock at 8A Big Smile

 

Enderman
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DoubleA wrote:
. lumen is a measurement of luminous flux, or the total amount of light produced by a light source whereas luminous intensity(candela) tells you how bright the light source is, which shows how far away from an object you can be and while still being able to see it?

Haha oops, did not read that one through.
Yes, you use an integrating sphere to turn the reading of intensity info flux, that’s what I meant.
They are proportional.