Esteban was right!

[Seden]

Good citizens,

I was reading on the Photonics Newsletter today and scientists are using lasers to detect chemicals in boxes at over a 100 meters. Even inside walls detection is possible with lasers and at the end of the article it mentions using it for geological detection. Look here:

http://www.photonicsonline.com/article.mvc/Finding-Explosives-With-Laser-Beams-0001?sectionCode=News&templateCode=EnhancedStandard&user=1951203&source=nl:33421

Long distance Raman Spectroscopy,this is great.

Randy

[WM6]

Good citizens,

I was reading on the Photonics Newsletter today and scientists are using lasers to detect chemicals in boxes at over a 100 meters. Even inside walls detection is possible with lasers and at the end of the article it mentions using it for geological detection. Look here:

http://www.photonicsonline.com/article.mvc/Finding-Explosives-With-Laser-Beams-0001?sectionCode=News&templateCode=EnhancedStandard&user=1951203&source=nl:33421

Long distance Raman Spectroscopy,this is great.

Randy

Nothing new.

Look at this 7 years old stuff:

http://www.signonsandiego.com/uniontrib/20051227/news_1n27detect.html

[Seden]

Almost true

Here's what IS new:
" a new method has now been developed to detect chemicals inside a container over a distance of more than a hundred meters."

The 7 year article does not make that claim.

Randy

[Geo]

Some times when i said that i saw a laser lrl that had the ability to detect objects from 70m, some members here irony me. So maybe it is time to read again all the threads from begin.
Also i own a laser lrl.

Regards

[WM6]

Some times when i said that i saw a laser lrl that had the ability to detect objects from 70m, some members here irony me. So maybe it is time to read again all the threads from begin.
Also i own a laser lrl.

Regards

Geo, there is no need that something what is working fine in theory and some lab tests, work the same in real world of your needs.

If your laser LRL is Bionic, it is useless (and at the same time very expensive) box usable as toy only.

[WM6]

Here's what IS new:
" a new method has now been developed to detect chemicals inside a container over a distance of more than a hundred meters."

The 7 year article does not make that claim.

Randy

If it can be mounted even on aircraft, this mean from great distance and it can be understood by itself that all landmines are in "containers" and not in form of free bulk explosive.

"The machine also could be mounted on an armored vehicle, on a robot or aboard a small unmanned aircraft.
Tong hopes to develop an instrument that can detect explosives from 110 yards away .."


But main problem with laser spectral detecting small amount of molecules at distance in real world (out of clean lab atmosphere) is that with distance we get huge and uncontrollable amount of unwanted molecules in air which totally cover and eliminate wanted molecules from detection.

[nelson]

Hi WM6

I agree with you on this, but if the device can have some sourse of discrimination like notch on MD, may be you can set it to detect only explosives particles.

I also will like to know how smoke detector for example detects smoke particles and no more than smoke? Is clear that this device is made to work only with smoke, but can this be mod to work to detect other kind of particles?

Regards

Nelson


But main problem with laser spectral detecting small amount of molecules at distance in real world (out of clean lab atmosphere) is that with distance we get huge and uncontrollable amount of unwanted molecules in air which totally cover and eliminate wanted molecules from detection.[/QUOTE]

[WM6]

Hi WM6

I agree with you on this, but if the device can have some sourse of discrimination like notch on MD, may be you can set it to detect only explosives particles.

I also will like to know how smoke detector for example detects smoke particles and no more than smoke? Is clear that this device is made to work only with smoke, but can this be mod to work to detect other kind of particles?

Regards

Yes, nelson, effectively it works like notch (of course with other technical solution) but notch we use in vicinity detectors and laser we tend to use as long range detectors.

Notch is usable in relatively clean soil. In soil full of different trash that cover wanted target signal, notch become completely unusable.

The same situation we get with laser at distance. We have 2 or 3 usable molecules at say 100m but before laser beam reach those molecules, beam hit billions of other trashy molecules in air, which give back totally mess of interference chaos and cover usable signals, if it was even created.

Smoke particles detector is another story, it cannot differentiate between different source of smoke.

[Dedevil]

Yes Estebans system workrd

But it is a difficult task to scan the earth with a laser beam the size of a head of a needle, it would take alot of swingig and you would probably end up spending any gold money on doctors fees to fix your sore elbow from swinging the laser around.
read more about it at http://www.nmp.csiro.au/ion.html
Estebans system was different and quite clever.
He modulated the laser output so the reflected wave is close to the modulated frequency, so you detect the reflected wave not the laser frequence.

rgds

[WM6]

But it is a difficult task to scan the earth with a laser beam the size of a head of a needle, it would take alot of swingig and you would probably end up spending any gold money on doctors fees to fix your sore elbow from swinging the laser around.
read more about it at http://www.nmp.csiro.au/ion.html
Estebans system was different and quite clever.
He modulated the laser output so the reflected wave is close to the modulated frequency, so you detect the reflected wave not the laser frequence.

rgds

Agree, Estebans system is working, but his system cannot detect nothing like gold or silver.

He pull the idea from laser spy microphone where voices modulate laser beam:

http://hacknmod.com/hack/how-to-long...ophone-spying/

Nice to play with such creation, but conceptually wrong and unusable in detecting things of value.

[nelson]

I understand WM6, but it must be a way to split that molecules, like a filter to let pass only gold molecules.
Anyway it is a very interesting technology to investigate.
Talking about pdk, do you have a good VLF oscillator to build has a coil stimulator for PDK. I need an oscillator capable to generate VFL btw 110 to 180 Khz or around this spectrum

Regards
Nelson

Yes, nelson, effectively it works like notch (of course with other technical solution) but notch we use in vicinity detectors and laser we tend to use as long range detectors.

Notch is usable in relatively clean soil. In soil full of different trash that cover wanted target signal, notch become completely unusable.

The same situation we get with laser at distance. We have 2 or 3 usable molecules at say 100m but before laser beam reach those molecules, beam hit billions of other trashy molecules in air, which give back totally mess of interference chaos and cover usable signals, if it was even created.

Smoke particles detector is another story, it cannot differentiate between different source of smoke.

[Geo]

But it is a difficult task to scan the earth with a laser beam the size of a head of a needle, it would take alot of swingig and you would probably end up spending any gold money on doctors fees to fix your sore elbow from swinging the laser around.

rgds

If you will try to detect the phenomenon then you don't need to do a lot of swinging. You must forget the theory with reflected signals.

Regards

[WM6]

it must be a way to split that molecules,

Maybe you can filter out some 1000s of unwanted disturbing molecules at distance of 100cm by using DSP technique, but you cannot filter out many billions of such trashy molecules found at distance of 100m and sense there one or two "gold" (which one?) molecules. Don't forget signal strength decreases by square of the distance, mean useful signal of remote targets are very weak in comparison with trashy signal everywhere on beam path. Science fiction.

[humhum]

laser lrl

Some times when i said that i saw a laser lrl that had the ability to detect objects from 70m, some members here irony me. So maybe it is time to read again all the threads from begin.
Also i own a laser lrl.

Regards

Hi Geo, can you post some photos from your laser lrl.

[Dedevil]

Crap!

Agree, Estebans system is working, but his system cannot detect nothing like gold or silver.

He pull the idea from laser spy microphone where voices modulate laser beam:

http://hacknmod.com/hack/how-to-long-range-laser-microphone-spying/

Nice to play with such creation, but conceptually wrong and unusable in detecting things of value.

Esteban's method has nothing to do with spy cameras. He used a modulated laser in the infared spectrum to transmit. And then detcted the bouncing back lower frequency modulating frequency. Discrimination is possible, but depth is very low due to the use of the IR laser for transmission. This is why i suggested using a MASER of a slightly lower frequency for transmission and then you may get depth and discrimination.

Please understand your technologies before posting quotes of "he is wrong" as you become and sound like a fool in front of everyone.

rgds