I'm going to "Laser" a pilot.

Hello FBI surveillance software?

Anyway, I am now in possession of one brand new "Jasper" DPSS 5mw laser from
bigha.com. That's the same laser used in the recent media hyped incidents
at KTEB. I'm going to test the claims that pilots can be visually impaired
empirically. (Guess who the pilot is.) The weather is perfect for
his. -20 and clear. I plan to try it at distance of about 3500' which is
as close as anyone is likely to get to a landing plane. I happen to work
near a perfect stretch of parking lot (one of the best places in a busy
metropolis to land if you really have to) which is perfect for this. It's
very runway-like. I'm going to do three things:

1. Measure the size of the beam at a measured distance.

2. Look into the beam for about 500ms after conditioning my eyes to usual
night flying light levels.

3. Have a skilled pistol marksman (cop friend) try to accurately hold the
beam steady at a measured distance both free hand and with support and see
what the wiggle area is.

If anyone else can think of anything else they'd like to see tried (no, not
in *my* plane) please post it here.

This isn't meant to be a scientific experiment or to become information used
instead of any government research or guidelines. OK?

moo

You're crazier than a bedbug. Hope you have a good source of slightly used
retinas.

Bob Gardner

"Happy Dog" wrote in message
. ..
Hello FBI surveillance software?

Anyway, I am now in possession of one brand new "Jasper" DPSS 5mw laser
from bigha.com. That's the same laser used in the recent media hyped
incidents at KTEB. I'm going to test the claims that pilots can be
visually impaired empirically. (Guess who the pilot is.) The weather is
perfect for his. -20 and clear. I plan to try it at distance of about
3500' which is as close as anyone is likely to get to a landing plane. I
happen to work near a perfect stretch of parking lot (one of the best
places in a busy metropolis to land if you really have to) which is
perfect for this. It's very runway-like. I'm going to do three things:

1. Measure the size of the beam at a measured distance.

2. Look into the beam for about 500ms after conditioning my eyes to usual
night flying light levels.

3. Have a skilled pistol marksman (cop friend) try to accurately hold the
beam steady at a measured distance both free hand and with support and see
what the wiggle area is.

If anyone else can think of anything else they'd like to see tried (no,
not in *my* plane) please post it here.

This isn't meant to be a scientific experiment or to become information
used instead of any government research or guidelines. OK?

moo

"Happy Dog" wrote in message

"Bob Gardner" wrote in message news:W92dnXX_
Hello FBI surveillance software?

Anyway, I am now in possession of one brand new "Jasper" DPSS 5mw laser
from bigha.com. That's the same laser used in the recent media hyped
incidents at KTEB. I'm going to test the claims that pilots can be
visually impaired empirically. (Guess who the pilot is.) The weather is
perfect for his. -20 and clear. I plan to try it at distance of about
3500' which is as close as anyone is likely to get to a landing plane. I
happen to work near a perfect stretch of parking lot (one of the best
places in a busy metropolis to land if you really have to) which is
perfect for this. It's very runway-like. I'm going to do three things:

1. Measure the size of the beam at a measured distance.

2. Look into the beam for about 500ms after conditioning my eyes to
usual night flying light levels.

3. Have a skilled pistol marksman (cop friend) try to accurately hold
the beam steady at a measured distance both free hand and with support
and see what the wiggle area is.

If anyone else can think of anything else they'd like to see tried (no,
not in *my* plane) please post it here.

This isn't meant to be a scientific experiment or to become information
used instead of any government research or guidelines. OK?

You're crazier than a bedbug. Hope you have a good source of slightly used
retinas.

There's no risk. I'm calculating safety margins for exposure with the
assumption that the unit produces double its rated power. It'll still be
bright though.

moo

Have fun. You'll see a fairly bright green flash, or halo, depending on
the aiming accuracy. Even with a 100 mW output, at 3500 feet any diode
laser output will have expanded to many feet in diameter. You do the
math. Retinal input will be on the order of 1 microwatt, assuming a 2
foot diameter beam at the reception distance.
This entire laser blinding scam is a load of hogwash. My HP35 calculator
had my initials burned into it's case with a 5 WATT argon laser about 30
years ago. You could put your hand into the beam at the output of the 1
meter long tube for several seconds before feeling any heat. Would I
look into the beam? Hell no. Would I look into the beam of a 100 mW
diode laser 3500 feet away? Hell yes. For as long as you'd like. $10 a
minute. Of course, if I was a United pilot, I'd be looking for any way
to recoup my pension...help, help, I've been shot in the eye by a
laser!!! Pay me, pay me! And if I was a media weasel, I wouldn't even
need an excuse to make up a story like this one.

Happy Dog wrote:
"Happy Dog" wrote in message


"Bob Gardner" wrote in message news:W92dnXX_

Hello FBI surveillance software?

Anyway, I am now in possession of one brand new "Jasper" DPSS 5mw laser
from bigha.com. That's the same laser used in the recent media hyped
incidents at KTEB. I'm going to test the claims that pilots can be
visually impaired empirically. (Guess who the pilot is.) The weather is
perfect for his. -20 and clear. I plan to try it at distance of about
3500' which is as close as anyone is likely to get to a landing plane. I
happen to work near a perfect stretch of parking lot (one of the best
places in a busy metropolis to land if you really have to) which is
perfect for this. It's very runway-like. I'm going to do three things:

1. Measure the size of the beam at a measured distance.

2. Look into the beam for about 500ms after conditioning my eyes to
usual night flying light levels.

3. Have a skilled pistol marksman (cop friend) try to accurately hold
the beam steady at a measured distance both free hand and with support
and see what the wiggle area is.

If anyone else can think of anything else they'd like to see tried (no,
not in *my* plane) please post it here.

This isn't meant to be a scientific experiment or to become information
used instead of any government research or guidelines. OK?


You're crazier than a bedbug. Hope you have a good source of slightly used
retinas.


There's no risk. I'm calculating safety margins for exposure with the
assumption that the unit produces double its rated power. It'll still be
bright though.

moo

Hey Happy Dog. Why don't you get a spot on "Myth Busters". I'll fly and
you aim the laser. Then we can swap positions and show the entire world
what a load of crap this entire laser thing is.

Happy Dog wrote:

Hello FBI surveillance software?

Anyway, I am now in possession of one brand new "Jasper" DPSS 5mw laser from
bigha.com. That's the same laser used in the recent media hyped incidents
at KTEB. I'm going to test the claims that pilots can be visually impaired
empirically. (Guess who the pilot is.) The weather is perfect for
his. -20 and clear. I plan to try it at distance of about 3500' which is
as close as anyone is likely to get to a landing plane. I happen to work
near a perfect stretch of parking lot (one of the best places in a busy
metropolis to land if you really have to) which is perfect for this. It's
very runway-like. I'm going to do three things:

1. Measure the size of the beam at a measured distance.

2. Look into the beam for about 500ms after conditioning my eyes to usual
night flying light levels.

3. Have a skilled pistol marksman (cop friend) try to accurately hold the
beam steady at a measured distance both free hand and with support and see
what the wiggle area is.

If anyone else can think of anything else they'd like to see tried (no, not
in *my* plane) please post it here.

This isn't meant to be a scientific experiment or to become information used
instead of any government research or guidelines. OK?

moo

If anyone else can think of anything else they'd like to see tried (no,
not in *my* plane) please post it here.

This isn't meant to be a scientific experiment or to become information
used instead of any government research or guidelines. OK?

moo

How about:
1. Acquire a standard optometrist eye chart.
[A television resolution chart would be a good substitute]
2. Before each exposure, determine visual acuity.
3. After each exposure, repeat acuity test
4. Start at a lower exposure duration and work up.
[This may require performing the test(s) on separate nights]
5. Do the whole thing during the day, facing away from the sun.
6. Chart your work

Hmmm, before step 1, check your medical insurance and have an
optometrist or opthomalogist do a retinal scan, before and after.

Happy Dog wrote:

...
This isn't meant to be a scientific experiment or to become information used
instead of any government research or guidelines. OK?

I think you are missing the point Happy Dog... Frying eyeballs at 3500ft
with a 5mw device is not the question. I suspect the terrorists want to
verify their ability to point a higher powered, possibly useful weapon.

As usual, the news media is doing whatever they can to provide helpful
feedback.

"Rip" wrote in message news:lG

Hey Happy Dog. Why don't you get a spot on "Myth Busters". I'll fly and
you aim the laser. Then we can swap positions and show the entire world
what a load of crap this entire laser thing is.

I *hate* publicity. Knock yourslef out.

moo

"Casey Wilson" N2310D @ gmail.com wrote in

1. Acquire a standard optometrist eye chart.
[A television resolution chart would be a good substitute]
2. Before each exposure, determine visual acuity.
3. After each exposure, repeat acuity test
4. Start at a lower exposure duration and work up.
[This may require performing the test(s) on separate nights]
5. Do the whole thing during the day, facing away from the sun.
6. Chart your work

Hmmm, before step 1, check your medical insurance and have an
optometrist or opthomalogist do a retinal scan, before and after.


Apart from the retinal scan, pointless. The claim is that tiny lasers can
blind pilots. It's bull****. There isn't even a valid theory behind it.
My work is just entertainment.

moo

Happy Dog wrote:

"Casey Wilson" N2310D @ gmail.com wrote in

Apart from the retinal scan, pointless. The claim is that tiny lasers can
blind pilots. It's bull****. There isn't even a valid theory behind it.
My work is just entertainment.

moo

Although I agree that it is impossible to hold a laser on a sufficiently
small area at the distances described (a 1 degree fluctuation causing a ca.
90 ft. movement at 1 mile if my math is correct), there is valid theory
behind it. Maximum permissible exposure when looking into a laser beam is a
function of exposure time.

For wavelengths of 400 nm to 1.4 um: [1]

t = 1 ns to 2x10^-5 s MPE = 0.0005 mJ cm^-2
t = 2x10^-5 s to 10 s MPE = 1.8xt^(3/4) mJ cm^-2
t 10 s MPE = 10 mJ cm^-2

Laser device in question has a rated power of 5 mW.
1 W = 1 J/s
5 mW = 5 mJ/s

Assuming under the worst case the beam spread results in a beam no bigger
than 1 square centimeter (and there are 2.54 centimeters in an inch), the
exposure NEVER exceeds the MPE, even for very long exposure times. In
reality the beam spread is much greater. A device I tested has a beam
spread of over 2 inches at 50 feet.

How accurately must one be to hold the 1 cm beam on target at the target
distance? Assuming a distance of 1 km, a 1 cm movement is equivalent to an
angular displacement of:

tan a = 1 cm / 1 km = 1 x 10^-2 / 1 x 10^3 = 1 x 10^-5
a =~ .00001 radians =~ 20 arc seconds

So, the whole thing doesn't wash. The power is insufficient, the beam spread
is too great, and the required pointing accuracy is too high.

[1] Jurgen R. Meyer-Arendt, M.D., "Introduction to Classical and Modern
Optics", 2nd ed.