Jack, permit me to add to your call for more focus on the soliton subject, while allowing me to digress a bit when it comes to fiber optic power levels, and eye-safety issues. These are not necessarily relevant to the discussion at hand, although they may be, but I'll pass them along as this message unfolds, just the same.
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I too would like to learn more about solitons. The discussion that Curt and I were having concerning line codes might render a fuller understanding if we went deep enough into how optical line coding is effected now, and what the differences would be using soliton technology. But the level we were going into was highly superficial with too many variables both in agreed upon lexicon and in actual implementations, at best, to be helpful, one could argue, and be correct.
I agree that we should jump to the more salient issues concerning where the obstacles exist to soliton deployment, if someone can deliver those, and what's being done, and by whom.
Curtis, I'd suggest you pick it up where you left off with your 50ps statement, before we digressed.
Simply providing a more powerful pulse with a much narrower width seems to be the direction that Curtis was pointing to, on the surface, but acceptable LASER emission and eye safety regs may come into play, here. Although the much shorter duration of the pulse might offset the higher amplitude of it, if we are talking about average or effective power levels.
I don't know for certain if this is a dominant concern in soliton research, but I would think so, simply from an intuitive standpoint. If it's not relevant to the discussion at hand, then we are no worse off here for the wear, anyway. This subject doesn't get the coverage it should in other areas, as well, such as in the free space systems that we discuss here from time to time, and which I allude to, below.
Eye safety could play big into these decisions. As they do in free space optical systems such as the LU OpticAir model. In the case of LU's infrared system they difuse the situation, so to speak, by spreading the beam through the free space medium (air), and then converging it back to its original spot form factor again, through optics, at the remote end. Having said that, however, I'm not sure how safe they are when an individual is casually viewing the panorama from the World Trade Center, for example, through a telescope, a pair of binoculars, a camera lens, or through some other optical aid.
But I could be all wet on this point where it relates to solitons. If someone knows how relevant this issue of eye safety is, please speak up.
Eye safety comes into play in the factory where network elements are manufactured and tested, and because of the fiber handling realities that technicians get involved with during implementation and troubleshooting exercises, as well as when fibers are left unterminated in the carrier office while connected to systems. Anyone with a premises distribution system in their office complex which employs fiber-optic outlets might notice that the fiber "jack" or receptacle at the wall level is always pointed in a downward direction, facing the floor, for these reasons.
You mentioned one of my posts, citing what Bell Labs was doing during the early Seventies. Actually, if you want to see what the Labs folks were really intrigued with at that time, go to the url below.
In '73, the first field tests over "multimode" fiber hadn't even been conducted yet, much less singlemode or anything that would support soliton carriage, today.
techstocks.com
Regards, Frank |
