HDTenEightyP/NetNews huggingface dataset:
From: kab@s1.gov (Keith Benton)
Newsgroups: sci.optics
Subject: Re: Do I want flat-field binoculars?
Date: 22 Jan 93 22:43:24 GMT
Reply-To: kab@s1.gov
Organization: Lawrence Livermore National Laboratory

In article 1jnqh1INNeiv@crcnis1.unl.edu, vporguen@unl.edu (victor porguen) writes:
>rsilvers@cirrus.nynexst.com (Robert Silvers) writes:
>
>
>>	I need to decide between two Fujinon binoculars.  They
>>are identical in quality, but one has more eye relief and is
>>of flat-field design.  The flat-field ones cost more, $500 instead
>>of $400.  I understand what this means, but aren't most camera
>>lenses curved field?  (except for copy-stand cameras?)  Is this
>>something I should care about?  
>
>>	I do not wear glasses, so I do not want to pay for the
>>extra eye relief.
>
>I must be not up to date on binoculars, because I cannot understand
>how a pair of binocular can be of "flat field" design. Binoculars are 
>supposed to be able to focus on everything between say, distance "x"
>and infinity. This is definitely not a "flat" field. It's about as
>non-flat as one can imagine.
>
>Cameras and microscope objectives, which have notoriously curved 
>fields unless corrected, are something else. Here, you might want to 
>have a very sharp, flat "field", either because your object is flat
>(microscopes) or because your sensor is flat (cameras). 
>
>But what do you do with "flat field" binoculars...? Look at a wall?
>
>As far as the eye relief, it can be extremely important, especially if
>you wear eyeglasses, and even if you do not - it's a lot more 
>comfortable to use high-eye-relief systems. But if you can live 
>without it, I would buy the least expensive pair.
>

I thought flat-field had to do with the field of view and not
depth of field. This means that the lenses are corrected so that
the whole field of view is in focus and not just the center of the
field of view with distortion out to the edges. 

---
	---------------------------------------------------------
	|             Keith Benton: kab@s1.gov                  |
	| ME!?!? Speak for anyone here!?!? HAHAHAHAHAHAHAHAHAHA |
	|             Standard Disclaimers apply                |
	---------------------------------------------------------
From: zrepachol@cc.curtin.edu.au
Newsgroups: sci.optics
Subject: Re: Objective lenses that work in UV
Date: 23 Jan 93 19:58:37 GMT
Organization: Curtin University of Technology

In article <14260@ecs.soton.ac.uk>, hnr@ecs.soton.ac.uk (Harvey Rutt) writes:
> I seem to recall UV transmitting microscope objectives are used in
> biology where they excite fluorescence with UV. 

These are not normaly corrected for UV imaging.

> Also there are
> certainly some so called 'fluorite' objectives (?CaF2), although I
> *think* this was used for superior chromatic aberration compensation
> in the visible, not for its good UV transmission.

True.

> As another contributor pointed out, true diffraction limited
> performance in the UV with high NA is probably not on commercially.
> 

Not so. A 'standard' micro mix is a special lens correct solely for one of the
Hg emision lines ( can't recall which one, but is in the extreme blue/near UV
range ) with glycerine imersion. Zeiss have/had a lens for this, but I can't
find my catalogue, so I have refrained from posting till now.

> The other area of work which does use very high resolution UV
> transmiting lenses is microelectronics, with Hg line excitation. Their
> lenses can cost hundreds of thousands!
> 

My info is that these are optimized for a very narrow working range, and are
quite mediocre out side it.

Names to try: Zeiss, Wild, Perkin Elmer, Olympus, Nikon, Rodenstock, Schneider.

~Paul
Newsgroups: sci.optics
From: ajackson@ernie.Princeton.EDU (Andrew William Jackson)
Subject: Re: Optical computing
Originator: news@nimaster
Organization: Princeton University
Date: Thu, 21 Jan 1993 06:45:47 GMT

In article <1993Jan20.210811.26931@EE.Stanford.EDU> siegman@EE.Stanford.EDU (Anthony E. Siegman) writes:
>
>		[ much deleted ]
>  
>  
>   To respond to a slightly different thread, not only did big
>companies like IBM, Dec and Intel decide not to pursue digital optical
>computing, but there's been little interest from small or venture
>capital firms either -- no digital optical Apple's, or Microsofts, or
>similar startups appearing out of any garages either.
>

Excellent observation!  There are no high-tech startups because there is no 
useful optical computing technology now in existance - useful meaning faster 
or cheaper or in any way better (besides cooler and newer) than semiconductor 
based computing.

ajackson@ernie.princeton.edu
From: billy@bnr.co.uk (Billy Khan)
Newsgroups: sci.optics
Subject: Help with OPTICS questions for MSc
Date: 25 Jan 1993 16:37:19 GMT
Organization: BNR Europe, New Southgate, London.
NNTP-Posting-Host: bnsgs213.bnr.co.uk

Hi,

I have been set a task which is to answer two questions and show the 
workings for how I derived the answers.  Unfortunatley I am having 
serious touble with them.  If there is anyone out there that can help 
me I would be very grateful.  

ok

firstly -

(1)	A 1.3um DFB laser incorporates a quarter-wave shifted grating of 
180nm pitch and has (To) of 65K. At 20 (Degrees C), it has a 15mA threshold 
current, slope efficiency 0.08m W/mA and when biased at a constant current of
75mA it exhibits a line width of 100MHz and an fo of 1.5GHz. If the temperature
is raised to 60 (Degrees C) and the slope efficiency remains unchanged, 
what are the new values of the line width and fo ? If dn<eff/dT = 2 * 10<-4
for the active region, by how much does the output wavelenght shift.

(note the answers are 127MHz;978MHz +3nm] need to know how 
to arrive at these answers.

(2)	State which light sources you would suggest utilising in each of the 
following proposed single mode fibre systems, and justify your selection:

-A trial 10 Gb/s, 100Km single span transmission system.

-A fibre optic link for connecting a remote microwave antenna at 14GHz to its
RF generation and control system 5km distant.

-A 50Mb/s data distribution bus to be installed in an aircraft to supply
video entertainment services to all passengers.

-A 100 Mb/s local area network connecting 60 Computer terminals in a large
office; each terminal must be capable of bidirectional communication.

-An experimental multi-wavelength ditribution network using 10 different
wave-lenghts, with adjacent wave lenghts seperated by 0.5nm, transmitted
on a single length of fibre.


Please, Please help someone as This has to be done by Thursday 28th Jan
for my MSc and I cant get help from anyone else.

Many Thanx in advance.

Billy.

-- 

			The TURBO-SWIFTER.
From: wellison@kuhub.cc.ukans.edu
Newsgroups: sci.optics
Subject: Laser Mania: More lasers for sell
Date: 26 Jan 93 15:30:04 GMT
Article-I.D.: kuhub.1993Jan26.093006.46770
Organization: University of Kansas Academic Computing Services



Got some different HeNe modules this time. These are idenical to the other
modules but produce 1.2mW to 1.5mW output. They also have the 
intergrated high voltage power supply that runs off of +12vdc. However, these
are multimode which means they have a wide beam. The beam can be narrowed down
with a minus lense though. Also, the side is milled out of the housing so that
the lasing action inside the plasma tube can be seen. These are great lasers
for teaching or training purposes. Due to the wide beam output, I am selling
these for $30 each plus 5$ shipping. 

I also scrounged a Spectra Physics model 124 HeNe laser and power supply. The
laser was manufactured in 1981, but the tube was re-gassed in 1991. It is in
excellent condition and produces +19mW. I am asking $2,000 or best offer plus
shipping.

For those interested in agron lasers, I have aquired two American 60X
multi-line heads. They produce about 80mW each in 488Nm to 514Nm (blue/green).
I am selling the heads for $1000 each. But, just for your info, Meredith
Instruments has Cyonics model 2201 argon lasers with power supplies that
produce 25mW blue only (488Nm) for $1200. They are selling the head for $695
(I'm thinking about one of those myself ;-) Thier address is:

Meredith Instruments
P.O. Box 1724
5035 N. 55th Ave
Glendale, AZ 85301
1-602-934-9387

In case anyone is wondering, I'm not making a profit on these lasers. I'm a
laser fanatic and I know there are others out there like me. I sell them for
what I paid for them to pass the saving on to you. Nothing I hate more than the
surplus dealers ripping people off with a cost to you of 2 or 3 times of what
they paid for it. Through years of beating the bushes, I have found out where
and how these guys get thier lasers. I'm paying the price they pay for them,
then pass that cost on, nothing more. If you have a specific laser need, let me
know and I will try to get the best price I can for you (definetly less than
what the surplus markets what for them).

-=-= Wes =-=-
From: ian@inf.ethz.ch (Ian)
Newsgroups: sci.nanotech
Subject: Re: Organic Machines?
Date: 25 Jan 93 22:24:52 GMT
Organization: Dept Biochemistry, University of Bristol, UK


>I did have the interesting thought that animals can be regarded as a
>cell's solution to the problem of boldly going where no cell has gone
>before; as a way of generating a cell-friendly local environment in
>globally hostile environments and as a means of travelling vast
>distances.

This is quite an orthodox view, it is necessary to bear in mind that
the cell is merely a device serving a similar function for genes/ribosomes
etc.

>It strikes me that in many cases nanotechnology might benefit from the
>same approach for much the same reasons. For example nanomachines
>might build a temporary containment structure to fulfill their
>environmental requirements while they did the real job.

At first, however, it is more reasonable to expect the user to provide the
environment.  Except, of course, where we are talking about very small
pieces of 'environment' such as nona-scafolding etc etc.

>More relevantly
>if you wanted a large group of nanomachines to do some job for you (we
>must think of a collective noun for a group of nanomachines)

Nanomass ? - Perhaps that should mean the sum total of all the nano-scale
             devices in a given environment (akin to biomass).

How about 'swarm' or 'hive'?

>[That's essentially what the Utility Fog is... By the way I'll have
> a presentation of the U. Fog at VISION-21 (the NASA thing this March).
> --JoSH]

OK, I'm ignorant, what's 'tility fog' ?

[Fill an environment (say, the inside of your house) with cell-sized
 robots.  They are able to simulate the presence (or absence) of 
 objects by grabbing each other in patterns -- sort of a 3D CRT.
 Maybe I ought to put a short description in the FAQ...
 --JoSH]
From: tsf@CS.CMU.EDU (Timothy Freeman)
Newsgroups: sci.nanotech
Subject: Re: Smart Micromachines
Date: 22 Jan 93 03:56:27 GMT
Followup-To: comp.ai.neural-nets

In article <Jan.19.22.29.25.1993.22986@planchet.rutgers.edu> nagle@netcom.com (John Nagle) writes:

   The state of the
   art is that machines have been built that can wander around in an office
   environment without getting into too much trouble, drive off-road for
   short distances on a good day, and drive on-road at 20MPH in a benign
   road environment (rumors of 60MPH at CMU - info?).

That's right, 55 MPH for about 22 miles.  The machine stayed in one
lane, and a person had to take over when the style of the road
changed.  It was the left lane, because there were exits from the
right lane and the system gets confused when presented with a fork in
the road.  It was a van steered by a neural network; the network was
trained by watching a recording of the scenery and the steering wheel
motions when a person drove on a road similar to the one that the
network eventually drove.  Check out Dean Pomerleau's thesis at CMU,
if you want more details.

This is at best marginally relevant to sci.nanotech.  Followups to
comp.ai.neural-nets, which Pomerleau reads (but I don't).  Pomerleau
looked at this post before I made it and agreed with my summary of his
work.
--
Tim Freeman <tsf@cs.cmu.edu>    CompuServe ID 71045,2267 checked occasionally.
When they took the fourth amendment, I was silent because I don't deal drugs.
When they took the sixth amendment, I kept quiet because I know I'm innocent.
When they took the second amendment, I said nothing because I don't own a gun.
Now they've come for the first amendment, and I can't say anything at all.
From: tsf@CS.CMU.EDU (Timothy Freeman)
Newsgroups: sci.nanotech
Subject: PD Molecular Modelling
Date: 22 Jan 93 03:58:08 GMT

In article <Jan.19.22.39.56.1993.23061@planchet.rutgers.edu> U53644@uicvm.uic.edu writes:

   [Although I do not share Mr. Dunphy's pessimism, I second his
   proposal empahtically... Before we can do this in more than a
   handwaving way, however, we need molecular simulation software.
   Does anyone know of any usable PD codes, or is there any interest
   in a sci.nanotech-based collaboration to produce such a beast?
   --JoSH]

There are free programs that can display collections of spheres (I
think one of them is called "Multi", and I could dig through my old
mail to find others).  A few years ago I looked for a PD program to do
the chemistry simulations and didn't find one.  Most of the
academically developed ones seem to be available for hundreds of
dollars from the Quantum Chemistry Program Exchange.  I hope the
authors receive a significant fraction of the fees; otherwise someone
is getting paid lots of money to do the job of an anonymous FTP
server.  It might be worth checking the archives of the comptutational
chemistry mailing list that was announced here a while ago to see if I
missed anything, or if something has come out since I stopped watching.

I would be interested in working on such a program if I were done with
my thesis.  From the MM2 and MM3 papers it doesn't look too hard,
assuming that no chemical reactions are happening in the system.  Does
anyone have any practical experience developing these?
--
Tim Freeman <tsf@cs.cmu.edu>    CompuServe ID 71045,2267 checked occasionally.
When they took the fourth amendment, I was silent because I don't deal drugs.
When they took the sixth amendment, I kept quiet because I know I'm innocent.
When they took the second amendment, I said nothing because I don't own a gun.
Now they've come for the first amendment, and I can't say anything at all.
From: mancini@fysik.uu.se (Derrick C. Mancini)
Newsgroups: sci.nanotech
Subject: Re: Homebrewed STM
Date: 27 Jan 93 04:54:11 GMT
Organization: Fysikum, Uppsala Universitet

In article <Jan.25.16.19.14.1993.9868@planchet.rutgers.edu>,
alfa@werple.apana.org.au (Glenn Durden) wrote:
> Since scanning rates in STM's arent quick, this effectively killed my 
> 'project', since I couldnt find a peizo electric device that would do what
> I needed (ie: deform to a given voltage).
>  So...  to any people who HAVE built one, what did you use?

Piezodrives are used.  With AC driving it, you can use relatively low
voltages if you run the material near a natural resonance.  To run these
babies in DC mode, you need thousands of volts and long enough pieces.
Also, there is a trick.  Many piezo materials deform best not in a linear
fashion, and you have to rig the mechanics appropriately.

Also, since I sent this info off to one of the correspondents, I thought
I would mention here for those who don't get Physics Today the company
that sells an instructional STM for $15,000:

Burleigh Instruments, Inc.
Burleigh Park, Fishers, NY 14453
716 924 9355

You supply the PC.  They have a money back guarantee.  This company
is well known in the piezoelectric positioning business.  I think that
is why they are trying to market an aggressively priced STM and can do
so: they know best how to make and use PZT driven equipment.  They have
a free video, according to the advertisement.

Derrick C. Mancini
Fysiska Institutionen  -  Uppsala Universitet
Box 530  S751 21  Uppsala  Sverige
mancini@fysik.uu.se
---------------------------------------------
"Are we having fun yet?"  -  Zippy
From: kamchar@ibm.cl.msu.edu
Newsgroups: sci.nanotech
Subject: Fear Regulation Poverty
Date: 27 Jan 93 04:50:58 GMT
Organization: Michigan State University

In article <Jan.19.22.41.18.1993.23082@planchet.rutgers.edu>  
cuhes@csv.warwick.ac.uk (Malcolm McMahon) writes:

> 4)   A "public key" encryption scheme is used for the ROM  program.  The 
> central  computer that compiles the ROM code first generates  a  private 
> and public key pair.
Sounds like an effective way to implement the "meterware and  
superdistribution" idea described on other groups and alluded to in a  
Foresight _Update_ article on "software component markets".  

Means
Something similar was discussed in a recent _Scientific American_.  Smart  
cards with separate AI processors and Public Key Encryption could make  
files only if the individual says OK.  The files are then examined by a  
network resource that can authenticate the files without knowledge of the  
individual's identity.  Thus we could create digital cash and place access  
control of an individual's credentials in the hands of the individual.

Implementation
I think that the materials authorization problem can be dealt with  
somehow.  But how would it be implemented?  Who decides what stuff I  
should have?  Libertarians fear the "evil governments who love regulation  
for its own sake".  Socialists fear "evil corporations who want to keep me  
poor even if my poverty is unnecessary."  Environmentalists fear  
"polluting manufacturing".  I dislike either/or thinking; and I think  
*all* these problems are serious.  But they have a common solution:  new  
technology properly used.  

Common Dangers
Likewise the three groups listed above will all hang separately if they  
don't hang together.  Here is the worst kind of regulation:  Not for  
safety but to infringe liberty and guarentee poverty.  The meterware idea  
is that software objects could function only on special machines which  
have downloaded (and purchased) authorization over the net.  Intellectual  
property rights could be administered by an equivalent of ASCAP.  Now I  
ask you who owns the rights to fire, the wheel, the bowl of rice?  If I  
get hungry I could scan a fish and duplicate it but not if life forms are  
restricted materials.

Can We Change?
Some say that the First World actually fears the development of the Third  
World and is willing to prevent such development because it operates on  
assumtions of a zero-sum game.  I hope this theory is incorrect.  Fear can  
be a good excuse for unecessary restriction and in my experience, it is  
difficult to convince people that there is no longer something to fear.

Forgive the length guys.  I'll take further talk to comp.society.futures  
if anybody's interested.

=========SunCat++++     | kamchar@ibm.cl.msu.edu
"A growth of knowledge is valuable only when it leads to a growth in  
wisdom."
--Ben Bova _Vision of the Future_
From: ttf@iti.org (Tihamer T. Toth-Fejel)
Newsgroups: sci.nanotech
Subject: Chemical Modeler
Date: 23 Jan 93 03:40:45 GMT

> or is there any interest in a sci.nanotech-based collaboration to produce
> such a beast?

Count me in, but I'm pretty ignorant, chemically.
I assume the program has to run in C or C++ and must run
in either Microsoft Windows 3.x, Mac, and Xwindows, and
preferably in all three. If its written in Visual Basic,
then it will run in pure DOS also - with 63 million users
out there, it might be worth it.

ttf@iti.org     (Tihamer T. Toth-Fejel)
Industrial Technology Institute, P.O. Box 1485, Ann Arbor, MI 48106
office: (313) 769-4248   fax: (313) 769-4064   home: (313) 662-4741
*----*----*----*Think of it as evolution in action*----*----*----*----*
From: jmains@aurora.engr.latech.edu (John P. Mains)
Newsgroups: sci.nanotech
Subject: Guided Micromachines
Date: 25 Jan 93 22:13:56 GMT
Article-I.D.: planchet.Jan.25.17.13.55.1993.10224
Organization: Louisiana Tech University

Hello again,

From postings in this group, it sounds like technology is presently
unable to produce extremely small programmable robots capable of
self-navigation.

My question now is, how small could you make a robot that will travel
to a specific source if it is given some type of either electric or
magnetic field?

-------
Thanx
JP Mains
La. Tech Biomedical Engineering

[In what environment?  In a vaccuum, a single electron would do it...
 --JoSH]
From: dbt@cellar.org
Newsgroups: sci.nanotech
Subject: Biology "versus" Nanotech
Date: 25 Jan 93 22:14:24 GMT
Article-I.D.: planchet.Jan.25.17.14.23.1993.10242
Organization: The Cellar BBS and public access system

As Drexler has taken pains to point out, biological systems -- living beings 
-- are kinds of molecular machines. Viral and genetic engineering are 
therefore kinds of nanotechnological engineering.

I don't think that nanotechnology will introduce a split between small-scale 
engineering and biology. On the contrary, biology (especially micro and 
ecological) and engineering are likely to be become much closer. As the 
"mechanics" of life is explored, and as biology-like aspects of engineering 
become more important, we'll probably see overlap. LOTS of overlap. 

The nanotechnology of acually moving individual molecules around may take a 
while to develop, but I concur with the opinion that biology-based nanotech 
is likely to be here soon, and may be seen to actually be upon us. 

And no, I don't think that we'll be raptured into heaven. One thing I 
*wouldn't* like to see is the formation of the Church of Jesus Christ, 
Nanotechnologist.

David Twery aka "Marquis de Freud" (dbt@cellar.org)
From: landman@hal.com (Howard Landman)
Newsgroups: sci.nanotech
Subject: Re: Smart Micromachines
Date: 27 Jan 93 04:51:47 GMT
Organization: HaL Computer Systems, Inc.

In article <Jan.17.22.55.15.1993.11274@planchet.rutgers.edu> tomk@netcom.com (Thomas H. Kunich) writes:
>Since I've worked
>on mechanical computers a good deal I feel that I have some experience that
>would suggest that these things are _not_ practical.

The February issue of Scientific American's cover article is by the folks in
England who actually built Babbage's Difference Engine 2.  About 10,000 parts,
a few bugs in the design that had to be fixed (including a serious problem
with initialization!), but basically, it works as designed.  There were some
very clever ideas to handle things like maximum carry (rolling over from
0,999,999,999,999,999,999,999,999,999,999 to
1,000,000,000,000,000,000,000,000,000,000) without generating large mechanical
stresses, and they worked even though they had not been built before.

One of their biggest problems was getting 'identical' parts worked to a fine
enough tolerance to actually be interchangeable.  They finally gave up, and
settled for just having the machine work.  With nanotech this shouldn't be a
major problem.  Atoms are very repeatable.

You were saying?

	Howard A. Landman
	landman@hal.com
From: merkle@parc.xerox.com (Ralph Merkle)
Newsgroups: sci.nanotech
Subject: Mopac FTP site
Date: 23 Jan 93 03:40:11 GMT

The following E-mail message (somewhat dated) discusses one site
which distributes Mopac via anonymous FTP.  The same site also
has Ampac.

The Journal of Computer-Aided Molecular Design, Volume 4, Number 1,
March 1990, is a special issue on Mopac and discusses it in great
detail.

-----------------------------------------------------------------
From secs.ucsc.edu!tcm-online-Sender Sun Jan 27 16:48:48 1991
Date:	Sun, 27 Jan 1991 15:59:16 PST
From:	wipke@secs.ucsc.edu (W. Todd Wipke)
To:	tcm-online@secs.UCSC.EDU
Subject: MOPAC 6.0 ftp site for vax and unix
Content-Length: 953