Device for conversion of light power to electric power (why doesn't this work)

 Device for conversion of light power to electric power


solar cell antenna
patent 4445050
direct conversion of light to electric power
april 24, 1984

http://patft.uspto.gov/netacgi/nph-Parser?u=%2Fnetahtml%2Fsrchnum.htm&Sect1=PTO1&Sect2=HITOFF&p=1&r=1&lP&f=G&d=PALL&s1D45050.PN.&OS=PN/4445050&RS=PN/4445050

Mark

  Mark wrote:

http://patft.uspto.gov/netacgi/nph-Parser?u=%2Fnetahtml%2Fsrchnum.htm&Sect1=PTO1&Sect2=HITOFF&p=1&r=1&lP&f=G&d=PALL&s1D45050.PN.&OS=PN/4445050&RS=PN/4445050

I like Google Patents (www.google.com/patents/) better, since it offers
images of the actual patent in addition to the OCR version.
http://www.google.com/patents?vid=USPAT4445050&id=8h0uAAAAEBAJ&dqD45050

Interesting idea -- it's sort of a crystal radio for light.

I'm wondering what kind of diodes could actually rectify an AC waveform
that's switching at a rate of 10^15 Hz.

And here's the real problem:

An incandescent source like the sun does not generate phase coherent
light.  In addition to the frequency diversity of the photons (hence the
"white" light that we perceive), you also are dealing with phase
diversity.  So one photon is caught by a dipole that happens to be
approximately the right length, and generates a teensy little pulse at
an extremely high frequency.  Another dipole catches another photon --
and let's say it just happens to be at the same frequency -- but it's at
a different phase.  Ick.  Partial or total cancellation.  Add in all the
different frequencies that are being caught and you have very little
signal to rectify.

Unless you plan to put one of these super-duper-ultra-hyper diode
bridges on each of the million-ish dipoles on the receiver chip, this
just ain't gonna work for incandescent light.

This wouldn't even work very well for rectifying the signal from a large
frequency and phase coherent laser, since the propagation delays between
all the dipoles and the rectifier bridge will cause phase cancellation,
unless you can do something very fancy with the transmission line paths
from the rectifiers.

It's cute, but I think the patent examiner wasn't even trying.  Or
perhaps he felt it was so worthless a patent that it didn't really
matter whether it was granted.

 
rlsusenet@NOSPAMPUHLEEZschnapp.org wrote:

http://patft.uspto.gov/netacgi/nph-Parser?u=%2Fnetahtml%2Fsrchnum.htm&Sect1=PTO1&Sect2=HITOFF&p=1&r=1&lP&f=G&d=PALL&s1D45050.PN.&OS=PN/4445050&RS=PN/4445050

It's not my idea...I should clarify, I am NOT the Mark that holds the
patent...


I don't agree with this.

At RF a crystal diode radio will receive non-coherent wideband noise
and rectify it to DC with no problem assuming the noise is large enough
to operate the diode etc, but the lack of cohernce is not an issue for
a diode.  In fact, the first radio transmitters were spark gap
non-coherent noise generators.

Mark

 Mark wrote:

http://patft.uspto.gov/netacgi/nph-Parser?u=%2Fnetahtml%2Fsrchnum.htm&Sect1=PTO1&Sect2=HITOFF&p=1&r=1&lP&f=G&d=PALL&s1D45050.PN.&OS=PN/4445050&RS=PN/4445050

I never thought you were the inventor.

And yes, I'm well aware of spark-gap transmitters, tube transmitters,
super-regen receivers, etc., etc.  I've got an extra class amateur radio
license.

The difference is that a crystal radio is not designed to gather energy
efficiently from a wideband signal.  It's designed to be sensitive at a
particular frequency, and derive _A SIGNAL_ from it.

In general, any particular signal IS coherent.  (When it's not, e.g.,
you get fading and on TV signals, ghosting.)

Trust me, this patent was never worth the money it took to get it
granted.  Nor even the postage.

 


That may be true but is is for the reason the other poster said about
implementing a dode that can operate at this frequency...
it is not about coherence....
you are correct a crystal radio is not designed to receive a wideband
signal, but it easily can be...the diode detector is not the limitation
to bandwidth



and please don't try to flaunt your credentials at me....
If you want to compare credentials in electronics with me , I am sure
you will not win...
I would rather compare ideas...

and by the way ghosting on TV has nothing to do with coherence of the
signal

Mark