HDTenEightyP/NetNews huggingface dataset:
Organization: University of Haifa - Mt. Carmel Haifa, Israel.
Date: Thursday, 1 Oct 1992 09:27:20 IST
From: <RXHFUN@HAIFAUVM.BITNET>
Newsgroups: sci.optics
Subject: protective monitor filters

Hello everyone,
I am looking for monitor filters vendors and manufacturers whose name I know,
but not their addresses. Can someone help?
1. Hoya (Japanese)
2. Viratek (German)
3. Balzers (German)
4. Randomex
5. Zenion Industries
6. Screen Data
7. Memorex Computer Supplies
8. GlareGone DRM

I would appreciate any kind of information about any of the above.
Thanx,
Ilana Merhav
Ergonomics and Human Factors Unit
University of Haifa, Israel
Newsgroups: sci.optics
From: ellis@noao.edu (Tim Ellis)
Subject: Infrared material properties
Organization: National Optical Astronomy Observatories, Tucson, AZ, USA
Date: Thu, 8 Oct 1992 21:28:42 GMT

opps

The title of the book is

Handbok of Infrared Optical Materials
edited by Paul Klocek
published by Marcel Dekker
copyright 1991
ISBN# 0-8247-8468-5


Newsgroups: sci.optics
From: zrepachol@cc.curtin.edu.au (Paul Repacholi)
Subject: Lens teesting info wanted
Organization: Curtin University of Technology
Date: Thu, 8 Oct 1992 20:36:10 GMT

Could some one please post pointer to testing of lenses, mainly
photographic, and releated matters. I have look through Kingslake. Ideal
would be an electronic OTF system of some type.

Thanks in advance

~Paul
From: hnr@ecs.soton.ac.uk (Harvey Rutt)
Newsgroups: sci.optics
Subject: Re: Ref on Thermal IR Properties?
Keywords: Thermal infrared, properties of materials
Date: 7 Oct 92 13:57:04 GMT

In <BvnGyD.615@cs.dal.ca> videen@cs.dal.ca (Gorden Videen) writes:

>There have been a number of requests for information on infrared/visible
>properties of various materials.  My first reference book off the shelf
>is "The Infrared Handbook" by Wolfe and Zissis.  More pages/$ than any
>other book I've bought recently.  

>-Gorden

iAgreed, but rather dated in its currently availble 3rd printing.
I believe SPIE are in the process of printing a new edition, not sure
how extensively updated, so look out for that.
The old 'Willow Run Report' ie
State of the Art Report Optical Materials for Infrared Instruments by
S S Ballard et al, Jan59, IRIA 2389-11-S from the
U of Michigan Willow Run Lab
is still useful as a compendium of basic data provided one remembers
its age!
Harvey Rutt Southampton UK

Newsgroups: sci.optics
From: kridnix@faraday.rice.edu (Alan Cheville)
Subject: Re: Seeing IR Leds !
Organization: Rice University
Date: Mon, 12 Oct 1992 18:02:34 GMT

In article <1992Oct8.095028.25054@cam-orl.co.uk>, dg@cam-orl.co.uk (Dave Garnett) writes:
|> I've got some small 'IR' Leds here - quoted peak emission 770nm,
|> spectral half bandwidth 30nm. Looking at them, I can clearly
|> see a lot of red light. (Material is GaAlAs).
|> 
|> So, the question is, assuming they've sent me the right stuff,
|> what sort of bandwidth should I expect ? If it is important
|> that there should be no visible radiation, what spec am I
|> looking for ?
|> 
|> Dave Garnett

You can see 770 nm.  Your eye however sees it as red light.  It can't distinguish
between colors above about 630 or 640 nm.  Longer wavelengths just look dimmer
for a given intensity.

-- 
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: gupta@ccwf.cc.utexas.edu (Sunil Gupta)
Newsgroups: sci.optics
Subject: CORRECTION OF FISH EYE LENS IMAGES
Date: 8 Oct 92 16:00:28 GMT
Article-I.D.: ut-emx.81297
Reply-To: gupta@ccwf.cc.utexas.edu (Sunil Gupta)


I am looking for information on correcting the barrel 
distorsion in the images obtained using a fish eye (wide
angle) lens. 

Any suggestion or information will be greatly appreciated.

Thanks in advance. 

Sunil Gupta
Newsgroups: sci.optics,sci.astro,sci.space
From: gawne@stsci.edu
Subject: IR detector discussion ???
Followup-To: sci.optics,sci.astro,sci.space,sci.materials,sci.chem,sci.physics
X-Newsgroups: sci.materials,sci.chem,sci.physics
Organization: Space Telescope Science Institute
Distribution: na
Date: Fri, 9 Oct 1992 17:13:40 GMT
X-From: gawne@stsci.edu

X-Xref: stsci sci.materials:760 sci.chem:4161 sci.physics:17415
X-Sender: news@stsci.edu
X-Organization: Space Telescope Science Institute
Distribution: na
X-Date: Thu, 8 Oct 1992 19:58:03 GMT

From Bill Gawne at the Space Telescope Science Institute
gawne@stsci.edu

Hi all.  Is there anyone out there in netland interested in
discussing IR detector materials?  I was thinking of InSb
Pt:Si, and HgCdTe in particular; but any lead chalcogenide
folks would be welcome too.

I'm interested in fundamental physics, crystallography,
and chemistry of the materials.  Also engineering involved
in producing detector arrays for both astronomical and
terrestrial applications.

Please e-mail or post replies to sci.materials.  Thanks,

-Bill
From: clark@bork.phy (Charles Clark)
Newsgroups: sci.optics
Subject: PostScript program for Fresnel zone plate
Date: 9 Oct 92 16:57:15 GMT

At the end of this posting there is a short PostScript program
that will generate a Fresnel zone plate on a laser printer.  Having
had several inquiries about this recently, I thought it might be of
interest to some readers of this news group.

Those of you with a few minutes to spare might enjoy printing out
two copies, one on paper and the other on a transparency, and observing
the patterns that emerge when they are overlaid with their centers
displaced.  This phenomenon has not yet failed to amaze and delight
anyone to whom I have shown it.  It is discussed in a paper by Prof.
Demkov and myself in the American Journal of Physics, v. 59, p. 158
(1991).

I was stimulated to post this by two telephone calls I had yesterday,
one from Prof. Demkov and the other from Prof. Duncan of the Johns
Hopkins University, who each suggested the same reason why this code does
not give a good working zone plate when printing on a transparency
(I should mention that Prof. Driver of Capetown University has obtained
quite good results by photograpically reducing the image, and using
the film negative as the zone plate).  The transparencies are probably
of nonuniform thickness on the scale of optical wavelengths, and this
would of course render the zone plate ineffective.  Prof. Duncan
mentioned that this problem could be solved by immersing the transparency
in an index-matching liquid.  This might provide an amusing demonstration
for a lecture.

Charles Clark
National Institute of Standards and Technology    


%!PS-Adobe-2.0
% The % symbol denotes a comment. Some PostScript
% printers (esp. those on UNIX systems) require
% the first line to be as presented in this listing,
% so that the following code is interpreted as
% PostScript.
/inch {72 mul} def
/blackCircle {0 360 arc
               0 setgray
               fill } def
/whiteCircle {0 360 arc
               1 setgray
               fill } def
/Xcenter 4.25 inch def
/Ycenter 5.5 inch def
/numberofZones 101 def
/centerZonesize 0.35 inch def
/nZsqrt numberofZones sqrt def 
/lastZone centerZonesize numberofZones sqrt mul def
newpath
Xcenter Ycenter lastZone blackCircle
numberofZones 1 sub -2 1 {/currentZone exch def
                    currentZone sqrt nZsqrt div lastZone mul
                    /whiteRadius exch def
                    Xcenter Ycenter whiteRadius whiteCircle
                    currentZone 1 sub
                    /currentZone exch def
                    currentZone sqrt nZsqrt div lastZone mul
                    /blackRadius exch def
                    Xcenter Ycenter blackRadius blackCircle } for
showpage
From: altner@ppc.lpc.ethz.ch (Stefan Altner)
Newsgroups: sci.optics
Subject: Piezo's and HV supply ???
Date: 12 Oct 92 18:56:39 GMT
Reply-To: altner@ppc.lpc.ethz.ch
Organization: ETH-Zuerich, Physical-Chemistry-Lab. - Switzerland

I want to build an external cavity diode laser system.  I need a piezo-trans-
lator to vary the length of the cavity. This piezo (together with its HV supply)
should be as stable as possible (very little noise). Maybe people who have already
built such a device can
 	recommend a combination of
		piezo
		HV supply
that will suit the purpose. Maybe also people out of the scanning tunnel micro-
scope "business" would know?

Thanks for any information, adresses etc.

Stefan Altner, 	
Lab. fuer Physikalische Chemie, ETH Zentrum, CH-8092 Zuerich, Switzerland
Tel +41 1 256 4383		Fax +41 1 252 3402
From: dleger@vms.eurokom.ie
Newsgroups: sci.optics
Subject: Refractive index of windscreens
Date: 13 Oct 92 13:40:54 CET
Organization: EuroKom Conferencing Service

I am looking for the index of refraction of glasses used for car windscreens;
does anybody have an idea of the value or know a reference.
Thanks.
From: foxd@silver.ucs.indiana.edu (daniel fox)
Newsgroups: sci.optics
Subject: Parametric Down Converters
Date: 14 Oct 92 14:03:53 GMT
Article-I.D.: usenet.Bw472I.JIq
Organization: Indiana University


Where can I find a source of parametric down converter crystals?  How much do
they normally cost?  I am also looking for some sort of very fast shutter that
can be triggered electrically.

                                        Daniel B. Fox
                                        KF9ET
.standard disclaimer
Newsgroups: sci.optics
From: wma6617@rigel.tamu.edu (ASHE, WILLIAM MONROE)
Subject: Re: Helmholtz Equation, answer to
Summary:  degenerate systems
News-Software: VAX/VMS VNEWS 1.41    
Organization: Texas A&M University, Academic Computing Services
Date: Mon, 12 Oct 1992 18:30:00 GMT

In article <1bb7tfINNr1l@manuel.anu.edu.au>, rwc124@rsphy1.anu.edu.au (Roderick Vance) writes...
> 
> 
>My question concerns the eigenvalue equation:
> 
> **stuff deleted**
>My question is: when can there be two or more linearly independent
>solutions psi1(x,y), psi2(x,y), ...  corresponding to the SAME 
>eigenvalue. 
> 
>I'd be most greatful for hints/thoughts about the above.
* You can have degenerate eigenvectors,(when more than 1 e-vect. corresponds
* to the same e-value.  These can occur in many instances.  The only way to
* find out about the degeneracies of a particular system is to work it out
* and see what overlaps what.  If someone knows a more general treatment of
* Classical degeneracies I would really like to hear about it.
* Bill Ashe
* Stored Ion and Laser Physics Lab
* Texas A&M University.
Newsgroups: sci.optics
From: siegman@EE.Stanford.EDU (Anthony E. Siegman)
Subject: Hermite-Gaussian and Laguerre-Gaussian Modes
Organization: Stanford University
Date: Thu, 8 Oct 92 19:26:55 GMT

We all know that the Hermite-gaussian modes of laser resonator theory
can be expanded in terms of a sum of Laguerre-gaussian modes, and vice
versa, since either the HG or LG modes are a complete set (right?).

But the actual expansion rules...can anyone cite a reference where
they're explicitly given?
From: senguptas@woods.ulowell.edu
Subject: YAG laser wanted
Organization: University of Lowell
Date: Thu, 15 Oct 1992 18:28:49 GMT


I am posting this for a friend. He is looking for an used YAG laser in good
condition. Output Power ca. 2-6 W in CW mode, Q-switching capability, TEM00
mode operation, with good beam quality. This will be used for research on
SHG devices and integrated optics. Price should be as reasonable as possible.
If you have a laser you would like to sell, or know of someone who does, please
send me a message. Lasers of somewhat different specifications may also be of
interest, if the price is reasonable. If you have had good luck buying from
a particular equipment dealer, we would like to hear about that too.
Thank you all for your help.

Sincerely,

Sandip

Sandip Sengupta
University of Massachusetts Lowell


Newsgroups: sci.optics
From: ellis@noao.edu (Tim Ellis)
Subject: Infrared properties
Organization: National Optical Astronomy Observatories, Tucson, AZ, USA
Date: Thu, 8 Oct 1992 21:23:18 GMT

The best source I've found in a while is:

	Handbook of Infrared Optical 
	edited by Paul Klocek
	published by Marcel Dekker
	copyright 1991
	ISBN# 0-8247-8468-5

This has both mechanical, and optical properties in a very
useful format.



Newsgroups: sci.optics
From: ellis@msl475a.erim.org (Ken Ellis)
Subject: Re: Ref on Thermal IR Properties?
In-reply-to: hnr@ecs.soton.ac.uk's message of 7 Oct 92 13:57:04 GMT
Organization: Environmental Research Institute of Michigan, Ann Arbor, Michigan
	<BvnGyD.615@cs.dal.ca> <13036@ecs.soton.ac.uk>
Date: 8 Oct 92 07:46:27


In <BvnGyD.615@cs.dal.ca> videen@cs.dal.ca (Gorden Videen) writes:

>There have been a number of requests for information on infrared/visible
>properties of various materials.  My first reference book off the shelf
>is "The Infrared Handbook" by Wolfe and Zissis.  More pages/$ than any
>other book I've bought recently.  

>-Gorden

And Harvey rutt responds:

>iAgreed, but rather dated in its currently availble 3rd printing.
>I believe SPIE are in the process of printing a new edition, not sure
>how extensively updated, so look out for that.
>The old 'Willow Run Report' ie
>State of the Art Report Optical Materials for Infrared Instruments by
>S S Ballard et al, Jan59, IRIA 2389-11-S from the
>U of Michigan Willow Run Lab
>is still useful as a compendium of basic data provided one remembers
>its age!
>Harvey Rutt Southampton UK

	The data in this report appears in the IR Handbook, although
not in as much detail. There was a supplement issued in 1961 with the
IRIA report number 2389-11-S1. My copy also has a number (DTIC?) AD
255 699 hand-written on the cover.

	IRIA is currently working on an 8 volume set entitled
"Infrared and Electro-Optical Systems Handbook" consisting of 45
chapters. The first volumes are expected to be available early next
year.
--
_____
\                                      |  Opinions expressed here are solely
 \   ERIM   Ken Ellis                  |  those of the author and do not
 /          ellis@erim.org             |  necessarily represent those of 
/____|                                 |  his employer.
From: dg@cam-orl.co.uk (Dave Garnett)
Newsgroups: sci.optics
Subject: Seeing IR Leds !
Date: 8 Oct 92 09:50:28 GMT
Reply-To: dg@cam-orl.co.uk (Dave Garnett)
Organization: Olivetti Reasearch Ltd, Cambridge, England

I've got some small 'IR' Leds here - quoted peak emission 770nm,
spectral half bandwidth 30nm. Looking at them, I can clearly
see a lot of red light. (Material is GaAlAs).

So, the question is, assuming they've sent me the right stuff,
what sort of bandwidth should I expect ? If it is important
that there should be no visible radiation, what spec am I
looking for ?

Dave Garnett
From: skoehler@tangelo.usc.edu (steffen koehler)
Newsgroups: sci.optics
Subject: Color of the moon
Date: 13 Oct 1992 11:13:15 -0700
Organization: University of Southern California, Los Angeles, CA
NNTP-Posting-Host: tangelo.usc.edu

Why is the moon white (or silver)colored?  Anyone know?

Using someone else's account to post, so please respond by e-mail only
to Mahgeref@alnitak.usc.edu

-- 
---------------------------------------------------------------------------
Steffen Koehler    |                      University of Southern California
skoehler@usc.edu   |                               Center for Laser Studies
(213) 740-4249     |    National Center for Integrated Photonics Technology
From: altner@ppc.lpc.ethz.ch (Stefan Altner)
Newsgroups: sci.optics
Subject: Piezo's and HV supply ???
Date: 12 Oct 92 18:56:51 GMT
Reply-To: altner@ppc.lpc.ethz.ch
Organization: ETH-Zuerich, Physical-Chemistry-Lab. - Switzerland

I want to build an external cavity diode laser system.  I need a piezo-trans-
lator to vary the length of the cavity. This piezo (together with its HV supply)
should be as stable as possible (very little noise). Maybe people who have already
built such a device can
 	recommend a combination of
		piezo
		HV supply
that will suit the purpose. Maybe also people out of the scanning tunnel micro-
scope "business" would know?

Thanks for any information, adresses etc.

Stefan Altner, 	
Lab. fuer Physikalische Chemie, ETH Zentrum, CH-8092 Zuerich, Switzerland
Tel +41 1 256 4383		Fax +41 1 252 3402
From: hanow@sscvx1.ssc.gov
Newsgroups: sci.nanotech
Subject: nano designer wannabe
Date: 15 Oct 92 23:22:40 GMT
Organization: Superconducting Super Collider Laboratory

Hello,
I am a mechanical engineer interested in moving my career in the direction
of nanotechnology.  I am functioning as a design engineer and am heavy into
CAD.  I also read a lot on molecular biology to learn about nature's 
molecular assemblers.  Can anybody suggest some good schools/classes/etc. 
available in the U.S. or other advice to procede toward the nano goal?
Greg.

[This seems to be a perennial question, and unfortunately there doesn't
 seem to be a perennial answer... I suspect that situation will change 
 over the next few years.  In the meantime I will collect any answers
 people send -- any takers?
 --JoSH]
From: REZAC@kuhub.cc.ukans.edu
Newsgroups: sci.nanotech
Subject: Re: Eliminating the need to sleep?
Date: 15 Oct 92 23:30:37 GMT

In article <Oct.8.12.08.41.1992.3855@planchet.rutgers.edu>, kmj@newt.phys.unsw.edu.au (Morris Jones) writes:
> Carl Sagan offers some interesting suggestions on the purpose of sleep
> in "The Dragons of Eden." He suggests that sleep was initially a way of
> immobilising some animals during the day who were too stupid to keep
> quiet and avoid predators. He then goes on to analyse the "core dump"
> hypothesis, suggesting that our brain filters through the day's memories
> when we sleep and decides what to retain. Perhaps we could spped the

Since the brain is divided into two hemispheres, its possible that the
core dumps go on rather frequently.  "Daydreaming" could be a state where
much of the processing is offloaded to the intuitive half of the brain so
the reasoning half can sleep.  Fugue states, where individuals are tightly
focussed on a specific task, could let the intuitive half do the core dump.

Core dump is probably a poor choice of words since some analysis is probably
involved.  I could be wrong, but I don't think there's any evidence to show
that memory is quite as complete as a core dump.  The analysis is probably
complicated enough that some of it needs the whole brain to perform, either 
in parallel or integrated -- thus, the need for sleep.

> process up to reduce the amount of "down time" we need, but I don't
> think we could eliminate sleep totally.

Me either. I might not mind nanobot cleaning up and doing routine maintenance,
but I'm sure I don't want them encoding my memories.
 
> Morris Jones. University of New South Wales. Happy International Space Year!
-- 
*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*
CHARLES REZAC   *   bitnet: REZAC@UKANVAX   internet: rezac@kuhub.cc.ukans.edu

[This thread is beginning to wander pretty far from the subject.
 It's probably about time to drop it...
 --JoSH]
From: kmj@newt.phys.unsw.edu.au (Morris Jones)
Newsgroups: sci.nanotech
Subject: Re: Eliminating the need to sleep?
Date: 8 Oct 92 16:08:42 GMT
Article-I.D.: planchet.Oct.8.12.08.41.1992.3855
Organization: School of Physics / UNSW

Carl Sagan offers some interesting suggestions on the purpose of sleep
in "The Dragons of Eden." He suggests that sleep was initially a way of
immobilising some animals during the day who were too stupid to keep
quiet and avoid predators. He then goes on to analyse the "core dump"
hypothesis, suggesting that our brain filters through the day's memories
when we sleep and decides what to retain. Perhaps we could spped the
process up to reduce the amount of "down time" we need, but I don't
think we could eliminate sleep totally.

Morris Jones. University of New South Wales. Happy International Space Year!
From: kambic@iccgcc.decnet.ab.com (Bonus, Iniquus, Celer - Delegitus Duo)
Newsgroups: sci.skeptic
Subject: Re: Exploration is not Technology
Date: 8 Oct 92 13:49:12 EST

In article <1992Oct7.220808.6718@odin.corp.sgi.com>, rodb@slugo.corp.sgi.com (Rod Beckwith) writes:
[...]
> 
> The evidence sir is the photographs that were returned by the viking probe.
> There is not enough evidence to prove beyond a shadow of a doubt what the
> structure is, so we must go back & re-photograph, re-analyze, re-evaluate,
> etc. Most skeptics say "What for, it's just a clump of eroded rock"
> 
> That Bobby my boy is what I am talking about. Skeptics will not open their
> eyes
> enough to allow that they might not know everything beforehand.
> 
> Just a wait & see attitude is all that it takes. What a difficult concept
> to grasp. 

He already said that.  Also, I should spend a lot of valuable Viking probe time
worrying about a possible face when it really does look like a pile of rocks to
most people a whole heck of a lot of image processing.

[He=R. McGrath, accidently erased attribution]  He's waiting for evidence which
contradicts most of the evidence already in hand.

GXKambic
sd
 			
Newsgroups: sci.skeptic
From: hes@unity.ncsu.edu (Henry E. Schaffer)
Subject: Re: Clinton and Creationism
Organization: North Carolina State University
Date: Mon, 12 Oct 1992 01:30:05 GMT

In article <1992Oct9.104128.15001@tpl68k0.tplrd.tpl.oz.au> keithh@tplrd.tpl.oz.au (Keith Harwood) writes:
> ...
>> Not USSR. Evidently Marxist theory said something like ``you shouldn't
>> inherit anything from your parents, not even blue eyes'', so Mendelian
>> genetics, Darwinian Evolution and even modern breeding techniques were
>> thrown out. There is a book, title ``Death of a science in the Soviet 
>> Union'' plusminus ten percent, author unknown; or look up `Lysenko' 
>> in a detailed history of the USSR.

Death of a Science in Russia by Conway Zirkle

--henry schaffer  n c state univ
Newsgroups: sci.skeptic
From: mcgrath@cs.uiuc.edu (Robert McGrath)
Subject: Re: Artificial movement of trees
Reply-To: mcgrath@cs.uiuc.edu
Organization: University of Illinois, Dept of Computer Science
Date: Wed, 14 Oct 1992 19:54:48 GMT

In article <1992Oct14.084718.20664@mnemosyne.cs.du.edu>, rberg@nyx.cs.du.edu (rosemarie berg) writes:
|> This is not a joke.
|> 
|> Artificial mechanisms for tree movement
|> 
|> Is there a possibility to make move trees, tree branches, leaves by any of the 
|> following means:
|> 
|> (1) by invisible beams of electricity?
|> 
|> (2) by using a force emitted from telephone lines?
|> 
|> (3) by putting some kind of object into the trees and using an exterior light 
|>     force, or a magnet, or the reflection of metallic objects either in the 
|>     trees on roofs or on the ground?
|> 
|> (4) by spraying either needles or leaves with a specific substance which would 
|>     react to an outside force or the sunlight (solar energy), solar panelling?
|> 
|> (5) by giving the trees an electrical shock?
|> 

What do you mean by "move"?  Trees move all the time, as they grow,
as the sun moves, and as the wind blows.  Presumably you mean some
"movement" other than that, but I'm not sure what you mean.  I also
wonder what conditions you are proposing, cause wild trees tend to be
in forests, and are surrounded by micro-climates that could make
a difference to some of these proposals.

Excluding outrageous energy levels (such as lightning) some of these 
ideas *might* be able to make a leaf or two flutter under ideal
circumstances.  Does that count?

What sort of "force" were you thinking of emitting from a telephone 
line, anyway?
Newsgroups: sci.skeptic
From: rberg@nyx.cs.du.edu (rosemarie berg)
Subject: Artificial movement of trees
Organization: Nyx, Public Access Unix @ U. of Denver Math/CS dept.
Date: Wed, 14 Oct 92 08:47:18 GMT

This is not a joke.

Artificial mechanisms for tree movement

Is there a possibility to make move trees, tree branches, leaves by any of the 
following means:

(1) by invisible beams of electricity?

(2) by using a force emitted from telephone lines?

(3) by putting some kind of object into the trees and using an exterior light 
    force, or a magnet, or the reflection of metallic objects either in the 
    trees on roofs or on the ground?

(4) by spraying either needles or leaves with a specific substance which would 
    react to an outside force or the sunlight (solar energy), solar panelling?

(5) by giving the trees an electrical shock?

Newsgroups: sci.skeptic