[Laser] Notes on Luxeon I, III's and Rebels and

[Clint Turner]

Hi Rado,

About the binning:

I suspect that like other manufacturers, the binning system is set up to 
accommodate a wide range of possible outcomes in the manufacturing 
process, ranging from old, obsolete devices of previous manufacture to 
devices that do not yet exist - but may be made in the future after 
further improvements.

 From what I have been able to tell, there are only 3-4 actual bins of 
devices available.  I suspect that the manufacturer simply would not 
destroy low-output devices, rather sell them for lower cost - which is 
what they do as there is a 25-30% price difference between the lowest 
and highest output binned devices.

As for the lumen output at a given current:  My suspicion is that both 
Lumileds and Luminus have approached a near-maximum as to how many of 
the photons produced may be extracted from the die, so it is not 
surprising that at a given current they wouldn't be very different from 
each other.  For maximum far-field flux, however, the maximum current 
density (which would imply "photons-per-square millimeter") would be 
desirable.  When comparing a Luxeon III running 1.1 amps with a CBT-54 
running at 8 amps, I measure an 8.5-8.75-fold difference between the two 
(depending on which optical transceiver that I check) - so I'll let you 
do the math.

73,

Clint
KA7OEI

> Message: 2
> Date: Sun, 19 Sep 2010 23:56:30 +0200
> From: "Vlacilik, Radovan"<Radovan.Vlacilik at siemens.com>
> Subject: Re: [Laser] Notes on Luxeon I, III's and Rebels and
> 	Phlatlights
> To: "Free Space LASER Communications"<laser at mailman.qth.net>
> Message-ID:
> 	<D1FEF394316C194395A2DA59959486E706F792EE at skbtss105a.ww300.siemens.net>
> 	
> Content-Type: text/plain;	charset="us-ascii"
>
> Hi Clint and optical group,
>
> I would like to ask about the Bins of the Luminus LEDs. For exaple
> mentioned Luminus CBT-40:
> http://www.luminus.com/stuff/contentmgr/files/0/5d1ae46c1a76dcc9f3de5b54
> 6fef72fc/miscdocs/pds_001229_rev_02_cbt_40_product_datasheet_illuminatio
> n.pdf
>
> When you look on the page 3, you can find the Bins for the Luminous Flux
> there. But I can not understand why there are such big differencies.
> The Red LEDs with the same drive current has its Luminous Flux spreaded
> from 120lm - 425lm?  The best one is three times better than a worst
> one? Is it caused by a differencies during the production?
>
> In my point of view when the technology of the LED production does not
> vary so much, than Luminous Flux of the LEDs with same current should be
> near the same too?
>
> I did not see such differencies with Lumileds for example. The standard
> Red Luxeon III does have better luminous flux with 1.5A, than worst
> CBT-40 with several Amps?!
>
> Many thanks for the any answer.
>
> Rado om2zz
>
>
>
>