5mm led mcd ratings

snowborder2645

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Hey I was wondering if someone could help me out. I'm trying to find out what the absolute brightest mcd rating for 5mm led bulbs are. All color's if possible. Thanks for the help.
 

RODALCO

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I have seen quotes on Ebay of 100k MC +. ( > 100,000 )
Not sure how true these numbers are.

I have used 10,000 and 20,000 MCAD LED's 5 mmØ.
These are very bright, especially the green ones.
The beam angle is quite narrow, typically 5 to 9 °.

It depends where you want to use them for.
 
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Marduke

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Don't be confused. mcd is not a rating of total brightness, it's simply a measure of throw. Total brightness is measured in lumens. There is no conversion between them.
 

snowborder2645

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Thank you for the information. I appreciate it. I would be using them to replace the Inova microlights. Also one more question if anyone knows what bulb is used in the x-color microlight by lri. Any help is appreciated.
 

snowborder2645

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thanks light sabre that calculator is exactly what i was looking for. One more thing about the actual bulb though. I'm almost positive it has a ic chip built into the bulb itself. Because if i were to take the bulb out of the x-color and put it in, say an inova microlight then it still has the same variations of color changing patterns.
 

space

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Don't be confused. mcd is not a rating of total brightness, it's simply a measure of throw. Total brightness is measured in lumens. There is no conversion between them.

I belive you have have it upside down here. Luminous intensity is measured in candela. Lumen describes the amount of light in a defined direction and don't say anaything about the intensity of the source. Total output is measured in lumen. (The defined direction is then 4*PI*sr.) A large emmiting area with "lower" intensity, can easyly have a higher lumen number than a very smal high intensity source focusing it in one direction.

more at http://en.wikipedia.org/wiki/Candela


space
 

Marduke

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I belive you have have it upside down here. Luminous intensity is measured in candela. Lumen describes the amount of light in a defined direction and don't say anaything about the intensity of the source. Total output is measured in lumen. (The defined direction is then 4*PI*sr.) A large emmiting area with "lower" intensity, can easyly have a higher lumen number than a very smal high intensity source focusing it in one direction.

more at http://en.wikipedia.org/wiki/Candela


space

Sorry, no, you have it upside down. Lumens is total brightness, Lux is throw.

That is why Lux is commonly measured at 1m with a cheap Lux meter, where lumens must be measured in a very expensive integrating sphere.
 

space

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Sorry, no, you have it upside down. Lumens is total brightness, Lux is throw.

That is why Lux is commonly measured at 1m with a cheap Lux meter, where lumens must be measured in a very expensive integrating sphere.

I think we agree for the most part. It boils down to the meaning/definition of "brightest" and "total brightness".

For me the "brightest" LED would mean the LED that would appear most intense at the brightest point. (I might be off here since English is not my mother language.) If this is the case, then the correct unit to the describe that parameter would be either candela or lux, both of which says something about the "concentration of light", amount of light/area = lumen/area. Lux uses the well defined square meter for area, and candela uses steradians. Steradians doesn't say anything about area unless one know the distance from source to measurement, but since most LEDS states the mcd-rating at the same distance (1m) it becomes a defined area. Hence both lux and mcd gives the same information.

If you by "total brightness" mean the average brightness/intensity in all directions, then I agree that lumen is the correct unit to describe that parameter.



space
 

Curt R

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Leaving science and definitions aside, we generally refer to Lumens as the total amount of light emitted from the LED as measured in an integrating sphere. Lux is a measurement of maximum light intensity at its' brightest point somewhere in the light pattern at a distance of one meter. Candela or candlepower or foot-candles is the same as Lux except the distance is one foot instead of one meter. 1000 mcd equals one Candela. Most conversion attempts at converting Lumens to Candela do not work in the real world. The primary angle and intensity of side spill when measured at only one point of reference with a Lux meter, can mean an error of up to 50% of total Lumen output. :(

Curt
 
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LED Finder

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Leaving science and definitions aside, we generally refer to Lumens as the total amount of light emitted from the LED as measured in an integrating sphere. Lux is a measurement of maximum light intensity at its' brightest point somewhere in the light pattern at a distance of one meter. Candela or candlepower or foot-candles is the same as Lux except the distance is one foot instead of one meter. 1000 mcd equals one Candela. Most conversion attempts at converting Lumens to Candela do not work in the real world. The primary angle and intensity of side spill when measured at only one point of reference with a Lux meter, can mean an error of up to 50% of total Lumen output. :(

Curt

As a novice i am looking for a short throw LED but needs to be bright i have just tested 13000mcd LED and was disapointed am going to try 2000mcd. Also looking for a wide throw LED with angles of over 130 degress. Any help will be appreciated. Please see what i am trying to achieve. attached. Any help will be appricated


Exhibition-signs-030.jpg
 
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