Plastic Optical Fiber bandwidth spec ?

[percy]

Bandwidth of an optical fiber(pof) is specified as Mhz-Km and typically a plastic optical fiber (pof - used in toslink cables) is about 5 Mhz-Km. I suppose that means if the pof was 1 Km long then the most bandwidth you can get is 5Mhz. But does that mean if the pof was only 1m long then its bandwidth is 500Mhz ? (or alteast in that order of magnitude – like 100+Mhz) ?

 

[jcx]

rapidly developing field, apparently graded index POF can boost the BW #

Ethernet POF trancievers are showing up in the market now

 

[simon7000]

You might want to look at the attenuation spec. Super Eska SH4001 is 190 db/KM!

 

[percy]

thanks for bringing that up - thats another spec I had the same question for.
What do these specs translate to for very short lengths ? i.e. 1 meter or less.
And this is all about 650nm (red).

 

[simon7000]

For short lengths the real issue is what you are using to send and receive the data! if you look at what is available the receiver is often what sets the data limit. 25 mbs is often the limit.

 

[percy]

It would be a typical toslink receiver/transmitter for spdif.
Now if its the receiver or transmitter that sets the data rate limit and if that is ~25Mb/s then that should be ample for cdda over toslink, correct ?

 

[simon7000]

Toslink should be under 6Mb/s. Plastic is fine. The limit would be about 4 M due to loss.

 

[qusp]

you could look at the lightpeak/thunderbolt type transceivers for higher bandwidth

$$$

 

[davidsrsb]

Very short fibre cables pass far more light than you would expect as high order modes are also transmitted. These have a far greater attenuation per metre than the modes present by the time you have gone 10m