Sonsivri

The LED has to be very bright. It will be used in a flashing ckt whose power supply is 6V-15V (I can use resistor to drop voltage). I am in dilemma which LED should I chose. Need your suggestion. :)

Sourcing from Digikey/Mouser/Farnell/ or others..

Cree XL series...  http://www.cree.com/LED-Components-and-Modules/Products/XLamp

The XM-L and XM-L2 are pretty much standard of in the industry for LED flashlights right now...

Don't use a resistor to regulate current on these high output LEDs, build (or purchase) a constant current driver...

BTW you can get a Cree XM-L and the driver on a star board for about $8 delivered on Ebay, IMO not even worth DIY unless you need a specific layout...

Thanks but I think I dont need it for lighting room or something. In fact I need very bright indicator LED, which will be used just for indication.

Search on ebay for Straw Hat LED... They're very bright, have a very wide viewing angle and a low profile. Quite inexpensive too.

looks like what I was searching :)

A big hug Cadence ! :D

Well you failed to mention it's purpose as an 'indicator' in your initial post but did request that it be 'very bright' apparently you are just looking for something brighter then your standard flux frosted indicator LEDs?

3mm, 5mm, 10mm, SMD or ?  Red, White, Blue, Green, Yellow, RGB or ?  Frosted or clear? 8°, 15°, 30°, 45° or ?

Sorry for the questions but my crystal ball is on the fritz this week...

Most generic indicator LEDs are under 50 mcd, and the field opens up after that, a 1000 mcd tight focus, clear can be painful to look directly at, but diffused or frosted and it can provide nice illumination...

When I want an LED to be visible in full sun, I generally choose 3000-10000 mcd LEDs, plenty of offerings in that range, but beware that range will easily bug your eyes out if you look directly at them...

Posted on: August 03, 2014, 11:12:24 23:12 - Automerged

---

Straw hats are nice if you want the huge wide angle of light that better simulates an incandescent bulbs 360° of light...  They work great as upgrades to older products that had incandescent bulbs as there is little noticeable difference in the light pattern when put behind say a traditional indicator lens...

My bad. I should have posted details.

In the range of 3000-10000 mcd, is there any LED which have lower power angle than straw head led ?

You mean the degree of light?  Sure 20°-30° is pretty much standard, while straw hats have 100° or greater generaly...

Just hit up Ebay and type 'super bright led XXX' where XXX is your color and/or package...  Unless you need color matched batches I would just get them on Ebay as they can be had much cheaper than the big electronics supply companies... 

Beware though that most of the LEDs sold on Ebay are 2nds that didn't match the color profile or standards of the manufacture and/or there was a higher failure rate in that batch...  I have used 10s of thousands of Ebay LEDs, I just test them before insertion generally there are few failures but sometimes you get a bad batch, and if you want to color match say for two LEDs that will be situated right next to each other, do a manual check...  Again most of the times the LEDs are fine, but I have had a few batches were say 1 in 20 or 50 was bad, or where there were 2 or 3 distinct color variations in the batch..

CocaCola
I think he is just putting a couple of brake light's on his skateboard

My skateboard also includes a bracket for a triangular "Slow Moving Vehicle" sign!

There are a range of RGB modules available where you can blink, fade or create any choice of colors as per your own choice. Individual RGB LED's are too available say 1 watt x 3 from Luxeon, Cree, Edison,  and a host of chineese options for dirt cheap.