HDTenEightyP/NetNews huggingface dataset:
From: ja@gnv.ifas.ufl.edu
Newsgroups: sci.optics
Subject: Raytrace progs ???
Date: 16 Aug 92 22:32:58 GMT

Hello Netters,

I'm posting this for a friend but send responses to me and I'll
relay them.
     John    ja@gnv.ifas.ufl.edu
------------------------------------------------------------

Are there any shareware, freeware, etc, programs for raytracing
available by FTP or any other way?  I'm making refractor telescope
objectives and would like programs to aid design and evaluation of
lens and mirror surfaces.  

I don't have a computer at present but I'm considering purchase of
a 486 sometime soon.  Please include hardware/software requirements
with any suggestions.

Thank you

Jan
-------------------------------------------------------------------
Newsgroups: sci.optics
From: benoit@netcom.com (BENOIT SCHILLINGS)
Subject: zero vibration shutter.
Date: Mon, 17 Aug 92 23:23:47 GMT
Organization: Netcom - Online Communication Services  (408 241-9760 guest) 

I'm looking for a way to make a zero (or very low) vibration
shutter.
I've been thinking of using lcd cristals, but it seems
that in the transparent state, i will still loose quite
a lot of transmission.
Any idea (not a $2000 one !).
The shutter clear diameter should be +- 1 inch and work
ok for openings of 0.1 sec to hours.  

Thanks, Benoit



benoit@netcom.com
benoit@be.com


Newsgroups: sci.optics
From: siegman@EE.Stanford.EDU (Anthony E. Siegman)
Subject: Re: Calibration of a PMT
Organization: Stanford University
Date: Wed, 12 Aug 92 20:16:17 GMT


The gain (i.e., multiplication) of a PMT is _extremely_ sensitive to
the applied voltage (maybe to the eighth power for an 8-anode PMT).
And, the absolute sensitivity of the photocathode is _extremely_
sensitive to age, processing and sample to sample variations,
poisoning and aging, temperature, history, and everything else (the
stated sensitivity curves are only rough indications of any tube's
actual sensitivity).  And both cathode sensivity and gain are likely
to vary quite widely from spot to spot on the cathode surface.

So, though I have never calibrated a PMT, in the ultraviolet or
elsewhere, I suspect it will be difficult to do, equally difficult to
maintain.  If you can get enough output to see your output with a Si
photodiode, you have a lot better chance of a realistic calbration
(espeically with the right form of Si diode).

Newsgroups: sci.optics
From: tatum@utdallas.edu (Jim Tatum)
Subject: Calibration of a PMT
Reply-To: $user@utdallas.edu
Organization: The University of Texas at Dallas, ACC
Date: Wed, 12 Aug 1992 18:58:02 GMT

Greetings from Texas...

I am working with on a SHG experiment using a visible diode laser source. 
I am getting a bit of UV light, but I need to do an absolute measurement of 
the optical power at 335nm. Unfortunately all I have to use is a PMT. I know the
responsivity of the PMT at this wavelength, but I need to know the gain as a 
function of bias. There are 8 annodes in the PMT. Has anyone done this sort 
of calibration before... 


Thanks for your replies..

-Jim
  
-- 
 Jim Tatum,  EE Graduate Student       USnail
 InterNet:   tatum@utdallas.edu        Engineering & Computer Science, MS EC33
 Bitnet:     tatum@utdallas            The University of Texas at Dallas
 Phone:      (214) 690-2994            PO Box 830688
 FAX:        (214) 690-2813            Richardson, Texas 75083-0688
From: jkollin@hardy.u.washington.edu (joel s. kollin)
Newsgroups: sci.optics
Subject: Re: construction of an isolation table
Date: 15 Aug 92 02:02:38 GMT
Organization: University of Washington, Seattle


Pretty much any book on homebrew holography (you should be able to find at least
two in your university's library) can offer suggestions.  The basic idea (read about 
the finer points in Newport and Melles Griot catalogues) is have a rigid surface on
top of something mushy, so that the time constant of the whole system is more than
a second.  The mushiness will dampen vibrations, and the rigidity is necessary to
keep everything stable.

Sand tables and granite slabs on top of inner tubes etc are typical, low cost 
solutions.  Test the table with an interferometer before wasting plates.

You can still get inner tubes for farm equipment, etc.  
Newsgroups: sci.optics
From: sprent@sol.surv.utas.edu.au (Tony Sprent)
Subject: laser scanner controller
Organization: University of Tasmania
Date: Wed, 19 Aug 1992 06:10:59 GMT

I used to have details of a laser beam pointing system which used 
an analog voltage controlled mirror (voltmeter type) to deflect the beam. 
Using two of these it is possible to raster scan a scene or control the movement 
of the beam by suitable computer control.

Can anyone give me details of suppliers or where I can get hold of one

Many thanks

Tony Sprent
Department of Surveying and Spatial Information
University of Tasmania
GPO Box 252C Hobart
Tasmania

Phone 61-02-202110 Fax 61-02-202110  International         
        002-202110       002-240282  Australia
From: hnr@ecs.soton.ac.uk (Harvey Rutt)
Newsgroups: sci.optics
Subject: Re: construction of an isolation table
Date: 14 Aug 92 08:46:39 GMT
Distribution: world,local

In <1992Aug13.152035@ece.arizona.edu> mikey@ece.arizona.edu (Michael Gribbons) writes:


>can anyone give me some references for the construction of an isolation
>table. the application is holography and the main problem is vibration
>from passing trains. email or post responses.

>thank you very much,
>mike

>>The 'standard' cheap simple solution is a suitable flat heavy plate
(steel, or a 'gravestone' from your local monumental mason, or
whatever suppliers of gravestones are called in the USA) supported on
three partly inflated car inner tubes.
Works pretty well, many schools etc have used it for holography - some
cash deprived Universities that can't afford Newport etc too!
Don't know if it will cope with your trains tho'.!
Harvey Rutt
Southampton University UK
From: A.J.Robinson@lut.ac.uk
Newsgroups: sci.optics
Subject: Re: Optical Noise
Date: 12 Aug 92 09:21:36 GMT
Reply-To: A.J.Robinson@lut.ac.uk (Alan Robinson)
Organization: Loughborough University, UK.

In article <19180001@hpfcbig.SDE.HP.COM> gt@hpfcbig.SDE.HP.COM (George Tatge) writes:
>... What is the phenomenon which causes "optical noise" for lack of
>a better term?  By this I mean that strange soup of lighter and
>darker spots and colors and floating amoeba like things that 
>is (almost) always "between" my eyes and whatever I'm looking at.
>
>99.99999% of the time I just ignore it (like I assume everybody does)
>but on occassion (like once a decade) I become curious enough to 
>ask around.
>
>Q1. Is this standard for everybody?
>

Its certainly standard for me. Most of the time I ignore it too but sometimes
(particularly when looking at a high contrast image, such as a window 
from inside a dark room) it can be a real pain.

>Q2. Does it have an official name?
>

I remember the term 'floaters' but I'm sure there's a better one.

>Q3. Is it all just noise in the optic nerves?
>

Don't think so.

>Q4. Is it real stuff floating on the eye which just looks suspended
>in midair?
>

Its real stuff floating IN the eye, but whether its in the aqueous or vitreous 
humour (or both) I don't know.

Alan.
Newsgroups: sci.optics
From: weverka@csn.org (Robert T. Weverka)
Subject: Re: Optical Noise
Organization: University of Colorado, Boulder
Date: Wed, 12 Aug 1992 13:54:42 GMT


Occasionally cells that line the eye die and flake off.
They float about.

Newsgroups: sci.optics
From: siegman@EE.Stanford.EDU (Anthony E. Siegman)
Subject: Re: OSA meeting
Organization: Stanford University
Date: Thu, 20 Aug 92 18:35:33 GMT

>After a solid week of trying, I've been unable to locate any
>information about the location of the Optical Society meeting in
>Albuquerque, the meeting hotel, their rates, etc. I'd appreciate these
>meeting details. I'd also like to know why the hell the Optical
>Society doesn't put this information in the journals.


   Well, the meeting announcements (and the OSA Meeting Department's
phone number) are in the 1 August 92 issue of Applied Optics, the 1
August 1992 issue of Optics Letters, and the July 1992 issue of JOSA
B, which are the most recent issues I pulled off the top of the pile
in my office.  And in Optics and Photonics News every month, for,
literally, years in advance.  And in direct mailings sent to every OSA
member (Including, I would suppose, student members, who can join OSA
and get OSA journals at very attractively low rates).
From: mgreen@cs.toronto.edu (Marc Green)
Newsgroups: sci.optics
Subject: OSA meeting
Date: 20 Aug 92 14:12:21 GMT
Organization: Department of Computer Science, University of Toronto

After a solid week of trying, I've been unable to locate any
information about the location of the Optical Society meeting in
Albuquerque, the meeting hotel, their rates, etc. I'd appreciate these
meeting details. I'd also like to know why the hell the Optical
Society doesn't put this information in the journals.

Marc Green
Trent University
Newsgroups: sci.optics
From: yjj@atlas.ctr.columbia.edu (Yuan Jiang)
Subject: Re: What is a (multiple) quantum well reflector...
Organization: Columbia University Center for Telecommunications Research
Date: Sat, 22 Aug 1992 15:03:22 GMT
X-Posted-From: atlas.ctr.columbia.edu
X-Posted-Through: sol.ctr.columbia.edu

In article <1992Aug18.235828.26283@u.washington.edu> ngrjn@milton.u.washington.edu (V Nagarajan) writes:
>	that is used as an end mirror to passively mode lock a solid-state
>	laser? Explanations, expositions, tutorials, references welcome.

I know that MQW (multi-quantum well) is used as saturable absorbers.
I guess it is used for this purpose as well in your case.  I don't
know how it functions as a reflector.

The advantage of use MQW is two fold.
1) The absorption edge can be tailored in a certain range.
2) The absorption peak is higher and sharper than regular semiconductor
material -- easier to reach saturation.
Newsgroups: sci.optics
From: odonovan@sciborg.UWaterloo.CA (Chris O'Donovan)
Subject: Wanted: Computer program that does simple optics.
Keywords: computer, optics
Organization: University of Waterloo
Date: Wed, 12 Aug 1992 20:00:56 GMT

Hi! I'm looking for a PC computer program that demonstrates elementary
optics (e.g. spherical lenses and mirrors) by drawing ray diagrams.

Thanks in advance,
-- 

Chris O'Donovan               |
odonovan@sciborg.uwaterloo.ca |
Xref: sparky sci.optics:882 sci.image.processing:423
From: IMAGING.CLUB@OFFICE.WANG.COM ("Imaging Club")
Newsgroups: sci.optics,sci.image.processing
Subject: Optikos optics newsletter
Date: 12 Aug 92 22:31:36 GMT
Organization: Mail to News Gateway at Wang Labs

I'm just getting a chance to start reading that
Optikos optics newletter that came out a couple
weeks ago.  The lead story is about a donation
they made to the Rochester Institute of Technology
for Imaging Science.  They've donated the
company's "breakthrough" VideoMTF system, the
first real-time, 2-dimensional MTF measurement
system, and the new release of their ACCOS
optical design software.  The RIT experimental
work has concentrated around the effects of
optical aberrations on subjective detection
and resolution.  The additional capabilities
will now allow RIT to extend the studies on
visual experimentation to real experiments
that use direct measurements of computer
simulations.  The instrumentation will be used
to compare various diffraction and geometrical
criteria for optimum focus and image quality.

Other work Optikos is doing relates to opthamology
(measuring scattering within the eye), projection
systems for measuring customers' optics, graphics,
fully automatic infrared test stations, prototype
equipment for blood analysis, and high speed
microfilm camera systems.

Other articles include MTF testing of intraocular
lenses, and optimization techniques for optical design
software.

Free subscriptions are available by calling Michele at
(617) 354-7557, or sending a note to Optikos at
286 Cardinal Medeiros Avenue, Cambridge, MA 02141.

Michael.Willett@OFFICE.Wang.com
Newsgroups: sci.optics
From: siegman@EE.Stanford.EDU (Anthony E. Siegman)
Subject: Re: Peterman's K - factor..
Keywords: unstable resonator , spontaneous emission, coupling
Organization: Stanford University
Date: Fri, 14 Aug 92 05:05:10 GMT

In article <hz5mkxp@lynx.unm.edu> swami@chtm.eece.unm.edu (Swami srinivasan) writes:
>
>	I need some references on something i heard a few months before,
>the Peterman's (sp?) K- factor.
>
>
>	 I heard that Prof. A. Siegman and a Soviet scientist have 
>worked on this, quite a long while ago. 


Not all that long ago (Phys. Rev. A, 1 February 1989).

A list of references on this, about 210 lines, is on its way to you by
email.  Anyone else wanting a copy should contact _you_, because I'll
be away on travel for nearly a month.

   --AES
From: swami@chtm.eece.unm.edu (Swami srinivasan)
Newsgroups: sci.optics
Subject: Peterman's K - factor..
Keywords: unstable resonator , spontaneous emission, coupling
Date: 13 Aug 92 17:58:58 GMT
Followup-To: swami@chtm.eece.unm.edu
Organization: University of New Mexico, Albuquerque


	I need some references on something i heard a few months before,
the Peterman's (sp?) K- factor.
				It has something to do with the
fraction of the spontaneous emission coupling into the modes of an
unstable resonator, or at least, that's what I gathered in a casual
conversation. It turns out that it may have a lot of significance in
my work, dealing with unstable resonator semiconductor lasers. Hence
the need for some insight...

	 I heard that Prof. A. Siegman and a Soviet scientist have 
worked on this, quite a long while ago. 

	Probably need to spend some time learning about this, and any
suggestions, explanations and references will be helpful.

	Danke Sehr!
							Swami Srinivasan

-------------------------------------------------------------------------
swaminathan srinivasan			swami@chtm.eece.unm.edu
center for high tech materials,		
eece, university of new mexico,		 Ph.#s: (505)-277-0239 (off.)
albuquerque, nm 87131, usa.	  		(505)-266-4349 (res.)
-------------------------------------------------------------------------
From: kridnix@faraday.rice.edu (Alan Cheville)
Newsgroups: sci.optics
Subject: Re: OSA meeting
Date: 20 Aug 1992 17:49:16 GMT
Organization: Rice University

I have a schedule for the OSA meeting.  Hope this helps...

Location:  Albuquerque Convention Center.

Fees:  Member- $285, Nonmenber- $345, Student- $95.

Hotels:  Hyatt, Doubletree, La Posada, Four Seasons, Holiday Inn Midtown,
and Marriott.  

Travel:  Delta-  ID No. J0708 or United- ID No. 524JW

More Info:  OSA meeting dept. (202) 223-0920.


-- 
Alan Cheville   	 # For this is the school of Babylon
Electrical Engineering	 # And at its hands we learn
Rice. U.		 # To walk into the furnaces
Houston		 	 # And whistle as we burn.
		 	 # 		-T. Blackburn
From: mikey@ece.arizona.edu (Michael Gribbons)
Newsgroups: sci.optics
Subject: construction of an isolation table
Date: 13 Aug 92 22:20:35 GMT
Reply-To: mikey@ece.arizona.edu (Michael Gribbons)
Distribution: world,local
Organization: University of Arizona Dept. of Electrical and Computer Engineering


can anyone give me some references for the construction of an isolation
table. the application is holography and the main problem is vibration
from passing trains. email or post responses.

thank you very much,
mike
From: mturner@aris.ss.uci.edu (Matthew Turner)
Newsgroups: sci.nanotech
Subject: Re: Snowballing nanotech
Date: 21 Aug 92 22:15:16 GMT
Organization: University of California, Irvine

In article <Aug.18.22.08.22.1992.16548@planchet.rutgers.edu>, tomk@netcom.com (Thomas H. Kunich) writes:
|> ...
|> 
|> In order to have a technology developed to any serious
|> level, don't you need to have a purpose for it? I mean
|> beside cloning ourselves indefinitely. :-)
|> 
|> I'm seeing some pretty fancy technological ideas flying
|> around here. (Thank heavens that technology has replaced
|> fantasy) But the industrial revolution occurred because
|> there was a need for products and the technology was 
|> developed to produce those products.
|> ...


There should be very direct and immediate applications in materials
engineering.  The ability to work on the molecular level allows the
construction of "faultless materials."

Examples:
	1) very strong, thin, and lightweight metal composites
	2) strong glasses
	3) wafer-scale integration in microchip manufacture...
           the ability to put say 100 or 1000 computers on a single wafer
                --thus eliminating the communications
                  problems that slow current computers down.
	4) cleaner polymer matrices ... thus stronger plastics.

etc...

-Matthion


======================================================================
All the world's an analog stage and digital players only get bit parts
======================================================================
                      mturner@aris.ss.uci.edu

[For near-term applications, I would expect to materials being done
 by conventional means, but nanotech-like (e.g. STM) methods used
 to study them.  Nanotech-built materials will have a hard time being
 economically competitive until there are self-reproducing assemblers.
 --JoSH]
From: vanderwerkend@lonex.rl.af.mil (Dan Vanderwerken)
Newsgroups: sci.nanotech
Subject: Re: Bootstrapping Nanotech
Date: 14 Aug 92 04:08:24 GMT
Organization: RL

In article <Aug.5.01.08.01.1992.15782@planchet.rutgers.edu> forrest@cup.portal.com writes:
>Suppose you had a working assembler arm and you were building a
>bearing. The bearing consists of an outer sleeve which is bonded
>rigidly to the base or frame, and an inner ring which rotates.
>During construction, the ring will have to be bonded to the frame
>somewhere to keep it from rotating while you work on it. After you
>finish constructing the ring, you will have to unbond it from the
>frame.
>
If I were going to build something like this on a macro scale, I'd machine
the sleeve, weld it to the frame, and then simply _insert_ the bearing/arm
assembly into it.  Why not do the same thing on the nano scale?

I don't see the need for temporary bonds.  Simply construct the pieces and
then fit them together.  If you need to hold something, have one assembler
hold a piece while the other works on it.

With a little creative design, you probably won't need to even need to hold
things in place.  You can make them "fit" together and then have an assembler
weld any necessary bonds.
 
>Anyone else thinking about such things?

I need to learn more about how proteins work first and how we'd program them
to do molecular construction for us.

---Dan---

-- 
Dan Van Der Werken          | 
Rome Laboratory/IRDO        | 
Griffiss AFB, NY 13440-5700 | 
(315) 330-3127              |
From: UGU00145@VM.UoGuelph.CA
Newsgroups: sci.nanotech
Subject: ideas for assemblers
Date: 14 Aug 92 04:28:59 GMT


For sometime I've been thinking of a ways of
making feasible molecular assemblers.  I've come up with a few
ideas, so let me know what everyone thinks of them.

1) My system is based on a mix of genetics and old punch card
operated computers, for instance I envision a long carbon strip (carbene?) that
is encoded with bits of information. Then we have a reader (or actual
assembler) that will move along the rod and depending upon the information
encoded in the strip, will direct the reader to assemble a certain structure.
This method uses pretty much the same principle that DNA uses to make protiens
and to self reproduce. There benefits of this method are that it allows for
a better controlled enviroment, the assembler could only remain locked onto
the carbon strip to function also there would be less of a chance of damage
caused by thermal vibration. Best of all this method would not need a
nanocomputer to run it. All though this method of molecular assembly is by
no means the universal assembler, it should give us a definable intermediate
goal to reach for, after all both DNA and punch card computers do work in the
same fashion. I would definitely like to hear what other readers think of
this method. I will be sending a more elaborate abstract to the Forsight
Institute, only after I hear what everyone else has to say though.

2) About a molecular "hand" , I have a very limited knowledge of chemistry,
but I do remember that some polymers can conduct electrons in the outer
electron shell. Now I do know that conductors can generate electromagnetic
fields so, what I was thinking was, could it be possible to use this as a
"hand" for an assembler arm? Sort of a electromagnet that grabs a nearby
atom and then moves it to a certain spot then turns off and allows the atom
to bond to whatever it was assembling. Hopefully the chemist's in this
confrence can tell me if this is feasible.

Greg

[Magnetism doesn't scale down to molecular sizes very well; look at
 using electrostatic forces instead.
 --JoSH]
From: portal!cup.portal.com!kr@pyramid.pyramid.com.UUX
Newsgroups: sci.nanotech
Subject: technical book "Nanosystems"
Date: 20 Aug 92 00:15:38 GMT

In article <11654.3.721.11 Re: Bootstrapping Nanotech>(8/13/92)
it was asked by naegle@icon.asd.sgi.com (David Naegle)
(as well earlier by someone else):

When will Eric Drexler's technical book "Nanosystems" be published ?

On Friday, 8/14/92, 40MB of PostScript was shipped to John Wiley & Sons,
the publisher of this book. According to the publisher, the printed
books should be in the bookstores by October, which is rather rapid.
I hope that the book will also appear on a similar time scale overseas, 
in Europe and in Japan.
The anticipated price is around US $25, a marvelously low price for
such a comprehensive technical handbook. This low price was achieved by
Eric's relentless efforts in Desktop Publishing to provide the printers
with a camera-ready product. Thank you very much for your hard work!

------- End - of - Message -----------------------
(responsibility for my personal opinions is mine)

Richard Stallman : "The more society becomes
        information instead of material objects,
        this question of whether
        a person can copy things
        will make the difference between

        a world of universal prosperity
     or a world of constant rat race."

__________________________________________________
kr@cup.portal.com            IIIII  M   M  M   M
Markus Krummenacker            I    MM MM  MM MM
(working for                   I    M M M  M M M
 The Institute for             I    M   M  M   M
 Molecular Manufacturing)      I    M   M  M   M
                             IIIII  M   M  M   M
From: mckendre@sal-sun61.usc.edu (Thomas Mc Kendree)
Newsgroups: sci.nanotech
Subject: Molecular Manufacturing Shortcut Group
Date: 20 Aug 92 00:12:38 GMT


  I would like to introduce to this newsgroup a (non-email) group that 
should be of interest to many.  It is a special chapter of the National
Space Society called the "Molecular Manufacturing Shortcut Group."  For
background, NSS is a non-profit group which supports space development,
and has as a long-term goal the large scale settlement of space.  The 
idea behind MMSG is that molecular manufacturing (in essence nanotechnology)
could make that long-term shorter--the time it takes to develop nanotech-
nology, and then settle Space, could be less than the time it will take
to settle Space with the currently evolving aerospace industry.  Thus, MMSG
was born to educate and promote people about nanotechnology, and how it could
apply to space developement.
  I suggest that any of you who are also interested in Space development
should join.  MMSG has not started out primarily for technical specialists,
but it needs some technical experts to help cull mistaken notions about
nanotechnology, and it has plenty of room for excited non-experts as well.
  Membership is $12 for one year.  Checks should be payable to MMSG.
Mail your name, address, email address and phone numbers to:

                              MMSG Membership
                              c/o Jocelyn Brown
                              6401 Deihl #409

[The message ends here (I checked). I do not suggest sending money to 
 this address, as the Post Office will simply throw it away.
 Hopefully a complete address will be forthcoming--it sounds like a good 
 group.
 --JoSH]