| Topic: |
Science > Physics |
| User: |
"Sam Wormley" |
| Date: |
17 Sep 2004 08:17:06 PM |
| Object: |
Antenna to catch visible light |
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
.
|
|
| User: "Myxococcus xanthus" |
|
| Title: Re: Antenna to catch visible light |
18 Sep 2004 05:04:47 AM |
|
|
"Sam Wormley" <swormley1@mchsi.com> wrote in message
news:m0M2d.66852$D%.22788@attbi_s51...
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
Very nice picture!
Incidentally, photosynthetic organisms have had oriented macromolecular
light-capturing complexes since very early in the evolution of life.
Although much smaller than nanotube assemblies, the complexes exhibit
several of the features attributed to carbon nanotube antennas, including
polarization sensitivity.
I selected the following papers because of their pretty pictures, which in
my opinion are just as nice as the one you pointed us to: atomic and
near-atomic reconstructions of the Photosystem I and Photosystem II
complexes, with data obtained through a variety of methods including
electron crystallography, xray crystallography, and image analysis of
thousands of electron microscope images.
Three-dimensional Structure of Chlamydomonas reinhardtii and Synechococcus
elongatus Photosystem II Complexes Allows for Comparison of Their
Oxygen-evolving Complex Organization*
http://www.uni-bielefeld.de/biologie/Zellphysiologie/Literatur/Nield%20et%20al.%202000.pdf
The chlorophyll-carotenoid proteins of oxygenetic photosynthesis
http://www.botany.hawaii.edu/Bot482/Chlorophyll%20-%20carotenoid%20LHPPC%20ARRPMB.pdf
Supramolecular organization of Photosystem I and lightharvesting complex I
in Chlamydomonas reinhardtii
http://www.ub.rug.nl/eldoc/dis/science/a.e.yakushevska/c6.pdf
Supramolecular organization of photosystem II and its light-harvesting
antenna in partially solubilized photosystem II membranes
http://www.nat.vu.nl/bio/pdf/99-15.pdf
Myxococcus xanthus
.
|
|
|
|
| User: "Helmut Wabnig **************" |
|
| Title: Re: Antenna to catch visible light |
18 Sep 2004 10:29:59 AM |
|
|
On Sat, 18 Sep 2004 01:17:06 GMT, Sam Wormley <swormley1@mchsi.com>
wrote:
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
Using micro-antenna arrays for directly converting light into
electric energy has been described decades ago by
Kraus in his book "Antennas".
Kraus (who died only recently) assigns that invention to
A.M. Marks, US patent 4,445,050, Apr. 24, 1984
w.
.
|
|
|
| User: "Edward Green" |
|
| Title: Re: Antenna to catch visible light |
19 Sep 2004 08:46:24 AM |
|
|
Helmut Wabnig <**************> wrote in message news:<lckok01b6euh5jhfmldcedfq9vlfngv34n@4ax.com>...
On Sat, 18 Sep 2004 01:17:06 GMT, Sam Wormley <swormley1@mchsi.com>
wrote:
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
Using micro-antenna arrays for directly converting light into
electric energy has been described decades ago by
Kraus in his book "Antennas".
Kraus (who died only recently) assigns that invention to
A.M. Marks, US patent 4,445,050, Apr. 24, 1984
Interesting -- and that patent will be expired now or very soon, so
that we all can build and market microantenna arrays!
What would be the advantages/disadvantages/practicality of this
approach, vs. a modern solid-state sensor array as used in digital
cameras?
.
|
|
|
| User: "" |
|
| Title: Re: Antenna to catch visible light |
19 Sep 2004 10:24:10 AM |
|
|
Edward Green <spamspamspam3@netzero.com> wrote:
Helmut Wabnig <**************> wrote in message news:<lckok01b6euh5jhfmldcedfq9vlfngv34n@4ax.com>...
On Sat, 18 Sep 2004 01:17:06 GMT, Sam Wormley <swormley1@mchsi.com>
wrote:
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
Using micro-antenna arrays for directly converting light into
electric energy has been described decades ago by
Kraus in his book "Antennas".
Kraus (who died only recently) assigns that invention to
A.M. Marks, US patent 4,445,050, Apr. 24, 1984
Interesting -- and that patent will be expired now or very soon, so
that we all can build and market microantenna arrays!
What would be the advantages/disadvantages/practicality of this
approach, vs. a modern solid-state sensor array as used in digital
cameras?
Nobody that I've heard is touting this as a method to build a camera.
The touted usage is TV transmission and solar conversion.
TV, or anything else like it is a non-starter.
TV over fiber has been around a long time.
AM modulation/demodulation of light has been around a long time.
Any other modulation scheme would require modulation/mixing/demodulation
technology that doesn't exist to build a "light radio".
Direct conversion of light to electrical energy, as in solar cells, may
have possibilities.
--
Jim Pennino
Remove -spam-sux to reply.
.
|
|
|
|
| User: "" |
|
| Title: Re: Antenna to catch visible light |
19 Sep 2004 07:49:38 AM |
|
|
In article <eca320d0.0409190546.5f288a92@posting.google.com>,
(Edward Green) wrote:
Helmut Wabnig <**************> wrote in message
news:<lckok01b6euh5jhfmldcedfq9vlfngv34n@4ax.com>...
On Sat, 18 Sep 2004 01:17:06 GMT, Sam Wormley <swormley1@mchsi.com>
wrote:
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
Using micro-antenna arrays for directly converting light into
electric energy has been described decades ago by
Kraus in his book "Antennas".
Kraus (who died only recently) assigns that invention to
A.M. Marks, US patent 4,445,050, Apr. 24, 1984
Interesting -- and that patent will be expired now or very soon, so
that we all can build and market microantenna arrays!
What would be the advantages/disadvantages/practicality of this
approach, vs. a modern solid-state sensor array as used in digital
cameras?
You could make one by hand, couldn't you? I just learned the
I could have made a radio with a razor blade and a wire strung
between two trees. I didn't know that.
/BAH
Subtract a hundred and four for e-mail.
.
|
|
|
| User: "Harry Conover" |
|
| Title: Re: Antenna to catch visible light |
19 Sep 2004 03:41:35 PM |
|
|
wrote in message news:<414d93e1$0$2668$61fed72c@news.rcn.com>...
I just learned that I could have made a radio with a razor blade and a wire strung between two trees. I didn't know that.
/BAH
Sadly, you omitted the most critical component, the rust, corrosion,
or crystaline material your razor blade must contact. A needle and a
piece of coal works just as well, or better. Anything semiconductive
with the non-linear electrical characteristics that permits
rectification of the radio carrier waves.
A resonant tuning circuit is also quite helpful, to separate stations.
You mean to say that you never built one of those things as a kid? :-(
Harry C.
.
|
|
|
| User: "" |
|
| Title: Re: Antenna to catch visible light |
20 Sep 2004 04:00:23 AM |
|
|
In article <7ce4e226.0409191241.258cc422@posting.google.com>,
(Harry Conover) wrote:
jmfbahciv@aol.com wrote in message
news:<414d93e1$0$2668$61fed72c@news.rcn.com>...
I just learned that I could have made a radio with a razor blade and a
wire strung between two trees. I didn't know that.
/BAH
Sadly, you omitted the most critical component, the rust, corrosion,
or crystaline material your razor blade must contact.
The rust was in the blade, IIRC. I don't understand this. How
can rust attract radio?
...A needle and a
piece of coal works just as well, or better. Anything semiconductive
with the non-linear electrical characteristics that permits
rectification of the radio carrier waves.
I think I did this stuff on paper when I did physics problems.
Somehow it doesn't translate into Reality :-).
A resonant tuning circuit is also quite helpful, to separate stations.
You mean to say that you never built one of those things as a kid? :-(
Nope. I never knew I could. I must have had a deprived childhood.
/BAH
Subtract a hundred and four for e-mail.
.
|
|
|
| User: "Richard Henry" |
|
| Title: Re: Antenna to catch visible light |
22 Sep 2004 07:45:45 AM |
|
|
<jmfbahciv@aol.com> wrote in message
news:414eafaf$0$2648$61fed72c@news.rcn.com...
In article <7ce4e226.0409191241.258cc422@posting.google.com>,
hhc314@yahoo.com (Harry Conover) wrote:
jmfbahciv@aol.com wrote in message
news:<414d93e1$0$2668$61fed72c@news.rcn.com>...
I just learned that I could have made a radio with a razor blade and a
wire strung between two trees. I didn't know that.
/BAH
Sadly, you omitted the most critical component, the rust, corrosion,
or crystaline material your razor blade must contact.
The rust was in the blade, IIRC. I don't understand this. How
can rust attract radio?
...A needle and a
piece of coal works just as well, or better. Anything semiconductive
with the non-linear electrical characteristics that permits
rectification of the radio carrier waves.
I think I did this stuff on paper when I did physics problems.
Somehow it doesn't translate into Reality :-).
A resonant tuning circuit is also quite helpful, to separate stations.
You mean to say that you never built one of those things as a kid? :-(
Nope. I never knew I could. I must have had a deprived childhood.
I learned that from some Hardy-Boys-style kids mystery book. You need a
"blue" razor blade, a wooden pencil, a safety pin, the speaker from an old
dial phone (which was easy to remove), some lengths of wire, and some tape
to hold the pieces together. Break the pencil in half, stick the safety pin
into the wood on the broken end of the pencil, contacting the graphite, and
use the sharp end of the pencil as a whisker to find a sweet spot on the
razor blade crystalline coating. Voila! Crystal radio!
.
|
|
|
|
| User: "Mark Fergerson" |
|
| Title: Re: Antenna to catch visible light |
20 Sep 2004 07:56:26 AM |
|
|
wrote:
In article <7ce4e226.0409191241.258cc422@posting.google.com>,
hhc314@yahoo.com (Harry Conover) wrote:
wrote in message
news:<414d93e1$0$2668$61fed72c@news.rcn.com>...
I just learned that I could have made a radio with a razor blade and a
wire strung between two trees. I didn't know that.
Sadly, you omitted the most critical component, the rust, corrosion,
or crystaline material your razor blade must contact.
The rust was in the blade, IIRC. I don't understand this. How
can rust attract radio?
Read this part:
...A needle and a
piece of coal works just as well, or better. Anything semiconductive
with the non-linear electrical characteristics that permits
rectification of the radio carrier waves.
It's the interface betwen the razor blade and the rust (the contact
point between the needle and the coal, the catwhisker and the galena,
the copper and copper oxide, n and p-type germanium or silicon, the
cathode and anode in a toob, and so on) that does the necessary
rectifying to detect the modulation envelope which encodes the audio
information you want. The interface conducts better in one direction
than the other, which is what "rectify" means here.
Gillette Blue Blades worked without rust because the blue coating
itself takes the place of the rust on an uncoated blade.
I think I did this stuff on paper when I did physics problems.
Somehow it doesn't translate into Reality :-).
Think about the first razor-blade radio built on a battlefield; some
grunt had an excellent "intuitive" grasp of the physics.
Likely the builder just didn't have a bit of coal handy.
A resonant tuning circuit is also quite helpful, to separate stations.
In a sparsely populated RF spectral environment, just cutting the
wire to the right length is adequate. Nowadays, not likely. Also,
cylindrical oatmeal boxes are harder to find.
You mean to say that you never built one of those things as a kid? :-(
Nope. I never knew I could. I must have had a deprived childhood.
Well, you coulda tried. Maybe your parental figures kept you too
busy. Idle hands, and all that. I'm eternally grateful that mine weren't
practicing Xtians. ;>)
Mark L. Fergerson
.
|
|
|
| User: "" |
|
| Title: Re: Antenna to catch visible light |
20 Sep 2004 07:45:49 AM |
|
|
In article <wrA3d.282459$Lj.251679@fed1read03>,
Mark Fergerson <nunya@biz.ness> wrote:
jmfbahciv@aol.com wrote:
In article <7ce4e226.0409191241.258cc422@posting.google.com>,
hhc314@yahoo.com (Harry Conover) wrote:
jmfbahciv@aol.com wrote in message
news:<414d93e1$0$2668$61fed72c@news.rcn.com>...
I just learned that I could have made a radio with a razor blade and a
wire strung between two trees. I didn't know that.
Sadly, you omitted the most critical component, the rust, corrosion,
or crystaline material your razor blade must contact.
The rust was in the blade, IIRC. I don't understand this. How
can rust attract radio?
Read this part:
...A needle and a
piece of coal works just as well, or better. Anything semiconductive
with the non-linear electrical characteristics that permits
rectification of the radio carrier waves.
It's the interface betwen the razor blade and the rust (the contact
point between the needle and the coal, the catwhisker and the galena,
the copper and copper oxide, n and p-type germanium or silicon, the
cathode and anode in a toob, and so on) that does the necessary
rectifying to detect the modulation envelope which encodes the audio
information you want. The interface conducts better in one direction
than the other, which is what "rectify" means here.
But somewhere along this line something has to change electron movements
into sound....which is beating air. I thought the string was to
capture the radio waves. They also talked a little bit about bed
springs collecting radio waves but our attention got diverted rather
quickly.
Gillette Blue Blades worked without rust because the blue coating
itself takes the place of the rust on an uncoated blade.
Yea, that's the blade the guys were talking about.
I think I did this stuff on paper when I did physics problems.
Somehow it doesn't translate into Reality :-).
Think about the first razor-blade radio built on a battlefield; some
grunt had an excellent "intuitive" grasp of the physics.
I didn't think it was possible for anybody to have a good
intuitive grasp of physics but then, that's because I didn't
have one.
Likely the builder just didn't have a bit of coal handy.
Coal used to be as common on the ground as pebbles. I'd find
coal bits everywhere.
A resonant tuning circuit is also quite helpful, to separate stations.
In a sparsely populated RF spectral environment, just cutting the
wire to the right length is adequate. Nowadays, not likely. Also,
cylindrical oatmeal boxes are harder to find.
[puzzled emoticon here] My larder is filled with round oatmeal
boxes.
You mean to say that you never built one of those things as a kid? :-(
Nope. I never knew I could. I must have had a deprived childhood.
Well, you coulda tried.
How can I try something I don't know existed?
..Maybe your parental figures kept you too
busy. Idle hands, and all that. I'm eternally grateful that mine weren't
practicing Xtians. ;>)
That boredom only happened on Sundays and Wednesday nights. I spent
my time on the river or in the woods. (Since the river was polluted,
I was not allowed to go in the river.) The rest of the time was
working. Going to school was my vacation.
/BAH
Subtract a hundred and four for e-mail.
.
|
|
|
| User: "Mark Fergerson" |
|
| Title: Re: Antenna to catch visible light |
22 Sep 2004 11:02:15 AM |
|
|
Some of my replies aren't getting through, so I'll retry:
jmfbahciv@aol.com wrote:
In article <wrA3d.282459$Lj.251679@fed1read03>,
Mark Fergerson <nunya@biz.ness> wrote:
jmfbahciv@aol.com wrote:
In article <7ce4e226.0409191241.258cc422@posting.google.com>,
hhc314@yahoo.com (Harry Conover) wrote:
jmfbahciv@aol.com wrote in message
news:<414d93e1$0$2668$61fed72c@news.rcn.com>...
I just learned that I could have made a radio with a razor blade
and a wire strung between two trees. I didn't know that.
Sadly, you omitted the most critical component, the rust, corrosion,
or crystaline material your razor blade must contact.
The rust was in the blade, IIRC. I don't understand this. How
can rust attract radio?
Read this part:
...A needle and a
piece of coal works just as well, or better. Anything semiconductive
with the non-linear electrical characteristics that permits
rectification of the radio carrier waves.
It's the interface betwen the razor blade and the rust (the contact
point between the needle and the coal, the catwhisker and the galena,
the copper and copper oxide, n and p-type germanium or silicon, the
cathode and anode in a toob, and so on) that does the necessary
rectifying to detect the modulation envelope which encodes the audio
information you want. The interface conducts better in one direction
than the other, which is what "rectify" means here.
But somewhere along this line something has to change electron movements
into sound....which is beating air. I thought the string was to
capture the radio waves. They also talked a little bit about bed
springs collecting radio waves but our attention got diverted rather
quickly.
Yep, you need a speaker or headphone of some sort, preferably the
latter. In them days, high-impedance headphones were huge, complicated
magnet/wire jobbies; today we have piezoelectric "crystal" earplug units
that work as well. "High-impedance" means they put a very small load on
the circuit; it was basically powered by the intercepted signal, which
is one reason you needed a lot of antenna.
Here's a frinst I found by Googling "foxhole radio":
http://members.aol.com/djadamson7/articles/foxhole.html
A bed spring is just a handy big, crappy antenna (does the actual
"radio attracting", so to speak).
Gillette Blue Blades worked without rust because the blue coating
itself takes the place of the rust on an uncoated blade.
Yea, that's the blade the guys were talking about.
I think I did this stuff on paper when I did physics problems.
Somehow it doesn't translate into Reality :-) .
Think about the first razor-blade radio built on a battlefield;
some grunt had an excellent "intuitive" grasp of the physics.
I didn't think it was possible for anybody to have a good intuitive
grasp of physics but then, that's because I didn't
have one.
It just means that one has had the concepts hammered into one's skull
early and often, so it's easier to figure out which available physical
stuff can have the desired properties for such a project. In my case, it
helped that a neighbor Amateur Radio enthusiast Elmered (Ham slang for
"tutored") me quite a bit.
Likely the builder just didn't have a bit of coal handy.
Coal used to be as common on the ground as pebbles. I'd find coal
bits everywhere.
In wartime such pebbles were collected for other uses, like
preventing death by freezing. ;>)
A resonant tuning circuit is also quite helpful, to separate stations.
In a sparsely populated RF spectral environment, just cutting the
wire to the right length is adequate. Nowadays, not likely. Also,
cylindrical oatmeal boxes are harder to find.
[puzzled emoticon here] My larder is filled with round oatmeal
boxes.
Well, around here (PHX, AZ), anyway. Oatmeal doesn't sell all that
well here, you see.
You mean to say that you never built one of those things as a kid? :-(
Nope. I never knew I could. I must have had a deprived childhood.
Well, you coulda tried.
How can I try something I don't know existed?
You could have intuited it, but you hadn't been adequately hammered
as per above.
..Maybe your parental figures kept you too busy. Idle hands, and all
that. I'm eternally grateful that mine weren't practicing Xtians. ;>)
That boredom only happened on Sundays and Wednesday nights. I spent
my time on the river or in the woods. (Since the river was polluted,
I was not allowed to go in the river.) The rest of the time was
working. Going to school was my vacation.
Between chores (sometimes during them) I found plenty of time to
exercise my budding intuition. Oh, well.
Mark L. Fergerson
.
|
|
|
|
|
|
|
|
|
|
|
| User: "Helmut Wabnig **************" |
|
| Title: Re: Antenna to catch visible light |
18 Sep 2004 01:17:00 PM |
|
|
On Sat, 18 Sep 2004 01:17:06 GMT, Sam Wormley <swormley1@mchsi.com>
wrote:
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
Using micro-antenna arrays for directly converting light into
electric energy has been described decades ago by
Kraus in his book "Antennas".
Kraus (who died only recently) assigns that invention to
A.M. Marks, US patent 4,445,050, Apr. 24, 1984
w.
.
|
|
|
|
| User: "Edward Green" |
|
| Title: Re: Antenna to catch visible light |
18 Sep 2004 09:40:14 AM |
|
|
Sam Wormley <swormley1@mchsi.com> wrote in message news:<m0M2d.66852$D%.22788@attbi_s51>...
Antenna to catch visible light
http://www.aip.org/png/2004/221.htm
Looks like a retina.
My squib was going to be "but isn't that a silvered telescope mirror?
.
|
|
|
|
|
Related Articles |
|
|
