Need some help on LED brightness

[mikezap99]

Hi everyone,

I'm planning on installing LED lights in the interior of my car. I've read about the legality, and it seems that green lights are legal on the interior.

I have found suppliers that offer a 23,000 mcd LED with a viewing angle of 15 degrees.
I want something that will produce a bright glow, as the light bars will be hidden from direct view. There will be an LED every 1/2" of the light bars. None of the commercial light bar manufacturers are able to supply me with either a lumen rating or a candela rating, so I have nothing to compare this with.

I have little experience with lighting but a fair amount of experience with circuits and the like.

Is 23,000 millicandela bright enough for my application?

 

[Mitchekj]

The viewing angle is what's disconcerting. 23000 mcd is fairly bright for these types of LEDs, but at 15 degrees, you're only talking about 1 to 2 lumens, and that's not incredibly bright by any standard. Any luck finding similar mcd ratings at a 30+ degree viewing angle?

Manufacturers sure do love the specmanship, don't they? I'm surprised no one's come out with a 1,000,000 mcd LED yet (oh, and a 0.01 degree viewing angle, but meh.)

 

[mikezap99]

Marktech Optoelectronics has this one:

http://www.marktechopto.com/Products/ultra-bright-leds.cfm?p=LC503TPG1-30G-A

7,500 mcd with a 30 degree viewing angle. I'm new to the LED world so I really don't know where to look or what suppliers are good. I need to find these in bulk too, as I'm going to order about 1500. Thanks!

 

[mikezap99]

http://www.marktechopto.com/Products/ultra-bright-leds.cfm?p=LO566NPG4-70G

Or this oval one, which is 70ºx40º and 39,813 mcd. Any comments? and is Marktech a good supplier or will I be disappointed?

 

[Resqueline]

When it comes to LED's and their application their spec don't tell it all and you'll either need experience or experiments. Iow. you're pretty much forced to get samples and try it out before deciding on a bulk buy. In this case it could seem that light distribution and scattering is a challenge, but being hidden from direct view it depends on a lot around the light bar itself. Sanding the surface of the LED's for instance is one way of diffusing the light if it turns out to be "spotty", but it may lower the apparent brightness a little.
You can use trigonometry to calculate the approximate lumen output of potential candidates, or you can visit this forum where some members have actually measured up many types and presented their real & useful data (lumens, color, beamspread, appearance, longevity).

 

[neon]

JUST SO you know 250,000 mcd is not uncommon i bought some and used them it is very hard to look at them directly I use them behind a water fountain water globe so the light is dispersed by the spinning globe it has a good effect.