bet

[laserwayne]

alright, i know this is a stupid question but a friend of mine believes its possible to collominate an led. i dont think it is so we made a bet. so is it possible to take an led and colliminate it

 

[MarioMaster]

do a quick search, there was a massive thread not long ago about this very issue

TL;DR version: no, you can't

 

[pullbangdead]

^Correct.

Light from LEDs is not coherent, therefore not able to be collimated.

What did you win in your bet?

 

[Switch]

Depends on what you consider collimation.Sometimes , focusing an LED with a reflector and lens is called collimation, more or less correct, but he may still argue with you. :-/

 

[Cyparagon]

Collimate:

1. to bring into line; make parallel.

I somehow doubt the beams of an LED are EVER going to be even CLOSE to parallel.

 

[rocketparrotlet]

Wish I could find that thread for you. As other people have said, even with fancy optics, it is not possible to collimate an LED because the light is not coherent like laser light. One person estimated that even with the best of optics and an extremely fancy set up, the light would not be coherent and the divergence would be at least 10 times that of a laser.

By the way, what laser is that in your avatar? It looks really cool.

-Mark

 

[RA_pierce]

I've done it, but it doesn't work nearly as well as a laser.

The lens had an 8 inch focal point and was positioned about 6 inches from the LED.
The result was a 2 inch diameter dot at 25 feet, and with less than 50% of the total output of the LED.
It works, but not well.

There is no way to get a beam from a LED that can match or even come close to a laser's.

This question has been answered many times...

 

[Zom-B]

a/b=c/d

where

a=die size, c=spot size,
b=distance from die to lens
d=distance from lens to spot

A die in a led is typically 0.2mm but if it has a round head (like standard leds) the die appears much larger and the beam actually gets much worse.