"Bare" LED's available?

[drizzle]

\"Bare\" LED\'s available?

My apologies if this has already been dealt with. I didn't find it in a quick search...

Is it possible to buy a flashlight quality LED that is not inside of a plastic package already? Basically I want one where the output is not already modified by the lens it is mounted into.

It seems like an obviously desirable thing to allow for a true point light source for use in a long throw flashlight.

 

[Echo63]

Re: \"Bare\" LED\'s available?

LEDs come mounted inside that little 5mm package - its the only way to get them
the Luxeons are available as just the Led mounted to a board (they also have a little polymer cap)
this polymer cap contains the phosphor that allows them to produce white light (i assume you want a white light)

if i got any of this wrong im sure the more knowledgable guys here will correct me

 

[HarryN]

Re: \"Bare\" LED\'s available?

Hi - In large quantities, the LED die for 5mm size are readily available. Cree and many of the other chip makers sell the parts at the wafer level (about 15,000 die per wafer) to packagers and OEMs. The price varies with die quality and color binning, sorting, etc, but a good estimate today is $ 0.05 for very low end to $ 0.60 at the higher end (per die).

Normally, Lumileds does not sell die, just packages.

I am not sure about small qty's of LED die, but frankly, wire bonding individual die is not trivial and requires either automatic equipment, or a microscope and patience.

Try Cree (North Carolina) or Lumei Opto (Los Angeles area) in the US for Blue and Green die. Osram has these as well as RED.

If you are looking for white, then you have an extra challenge to either mix RGB (which kind of messes up the point source concept) or you need the yellow phosphor + a blue die to make white. Usually, the phos is mixed with the encapsulating epoxy in the packaged die.

 

[gwbaltzell]

Re: \"Bare\" LED\'s available?

There is something between "bare" die and packaged (epoxy encased) "lamps". Its surface mounts. A search should turn up more info.

 

[Zelandeth]

Re: \"Bare\" LED\'s available?

Either that or the "flat" lensed expoy packages. Though they do alter the beam somewhat anyway.