I could be completely wrong here so feel free to correct me, but are we not talking about something completely different to the lecturer's l@ser pointer?
Those narrow beam devices have been used to attack bus drivers etc at short range, but I would doubt they are powerful enough or can be directed accurately enough to be more than the briefest flicker in the eyline of a pilot in flight.
There is obviousle something else out there that is far more dangerous and has no obvious 'practical' application.
I remember driving home one evening, not quite dark, and suddenly one of the large reflective roadsigns ahead lit up a very unnatural and vivid green colour. Not just a dot, but the whole roadsign! A little further on the same thing happened again and I realised that someone in the car in front was firing off something through the windscreen. I suspect this is what we are worrying about here?
These high-power ( > 1mW ) green l@ser devices are actually far too powerful to be used as 'pointers' in presentations or lectures, as they are so powerful! The reflected light energy is blinding to the presenter!! (similar to the effect on the road signs mentioned).
I'm not sure of their initial concieved use, be it military or otherwise but I do know they have found a use within the amateur astronomy circuit .where they were used as 'star pointers' (to align telescopes and to point out stars to others). They are falling out of favour however, due to the issues surrounding pilot blinding incidents.
The only real way to stop this IMHO, would be to reclassify any l@ser pointer with a power output > 5 mW as a form of potentially offensive weapon, perhaps introducing a licencing scheme such as exists for firearms to allow for legitimate uses.
Don't try taking any type of l@ser into the UAE as they are banned. they make no distinction between types (1,2,3,4). Pen l@sers or other similar l@ser pointy devices in hold or hand baggage will be confiscated and your name (passport details) will be added to the bad boy list!
First recorded 'attack' by green l@ser in Abu Dhabi was reported by an Etihad crew in 2006 on approach to AUH. The crew did the right thing and reported the incident to ATC who turned out the local police, no one was apprehended. The incident was reported in the local press about a week later and within a couple of days of the newspaper story numerous sightings of green and red l@sers were being reported around the Emirate. Seems the local boys had discovered a new plaything! Seems things have gone quiet these days thankfully.
Unaware that they were doing anything wrong the GCAA gave out 'pen l@sers' to anyone who visited their stand at an aviation exhibition in the UAE earlier this year! Boy that was embarassing!
Did King Harold lose and eye to a green or red l@ser, maybe I'm getting my history confused?
It's ludicrous that these things are legal at all in most countries. What gets me is that even a 125mW l@ser may or may not light cigarettes but it will still pop a balloon with ease. They should be treated like guns, only a person with a valid licence after an evaluation should be allowed to buy such things.
The basic rule with diode l@sers is this. The more powerful the beam, the quicker it expands in diameter. The beam is focused such that at a very small distance from the aperture, you might be able to light a cigarette...or melt a hole in a black plastic bag. Prior to, and beyond this small area...the beam will NOT light a cigarette nor melt black plastic.
We must not succumb to the image of the "Star Trek" type phaser beam....they all disperse with the square of the distance away. As the knowledgeable poster on Page one said....the best l@sers shot at the moon are 5 times the moon's diameter when they arrive there. If you were to look at the Earth from the moon (directly into the beam) you would most certainly NOT notice it.....it is that diverged.
For aircraft.....the beam operate the same way. It is very much wider (and hence weaker) than the millimeter beam width at the aperature. Combine this with topside cockpit windows, layed down at 45 degrees or more to the vertical, makes the beam pale in comparison to the landing lights on your wingtips.
IMO, people should not aim their l@sers at planes and helicopters....in the rare instance where the impinging beam might refract in such a way as to briefly distract the pilot flying. And as such I do not think the "hang 'em high" attitude needs to be taken in light of the well known facts and physics of collimated(sp) monochrome light.
The basic rule with diode l@sers is this. The more powerful the beam, the quicker it expands in diameter.
Actually not always true, at least at the low end of the power ratings in my opinion. Many of the more powerful DPSS l@sers have much better divergence (e.g. less than 1.5 mrad) than a 5mw pointer. Some of the cheaper brands like New Wish use plastic optics so they do spread more regardless of power.
For all you rocket scientists, here's a technical discussion of l@ser beam divergence:
As the knowledgeable poster on Page one said....the best l@sers shot at the moon are 5 times the moon's diameter when they arrive there.
I have to raise the B.S. flag on this gem of knowledge as well. Five times the moon's diameter would imply a beam divergence of 2.5 degrees, the astronomical l@sers (and even l@ser pointers) do a lot better than that. From a recent article about the Lunar l@ser Ranging Experiment:
A l@ser beam that starts out from a telescope on earth at about 1 meter width slowly diverges and is blurred by the atmosphere until it is about 10 km wide on the surface of the moon.
We must not succumb to the image of the "Star Trek" type phaser beam....they all disperse with the square of the distance away. As the knowledgeable poster on Page one said....the best l@sers shot at the moon are 5 times the moon's diameter when they arrive there.
Not that it matters - but the best l@sers could make a spot on the moon about 2 km in diameter.
What were those glasses called that were very popular some yaers ago. You know the ones with the active filter which reacted quickly to changing light intensity. Reactolite ? - supposedly a derivative of something developed for use by the forces in " Special conditions".
Some might think this a bit extreme in these tree hugging,bunny s*agging days,but I would subject these scroates to a dose of their own l@ser device and then ask them to walk a 4" wooden beam.............which just happened to be suspended between two extremely high buildings Post the results on Youtube and then see if it happens again.Maybe I should start a website....Letsstopscumbags.com.
Just phoned the Home Office re this problem. L@zers? Pilots? Eye damage? Safety of aircraft? They appear to know nothing about the problem. However did give me an e-mail address where the issue could be raised with the Government. firstname.lastname@example.org Please write, just sent mine.
Having had one of these l@sers targetted at my aircraft this week I can say that they are powerful enough to cause discomfort and distraction at 2,000' with the briefest of exposure. Ban them and prosecute - there is no debate.
Freely available from ebay, and as you can see - a little more powerful than you suggest.
These idiots need to be prosecuted and put in prison. There is no valid reason for a normal person owning one of these.
Well I own a <1mW green pointer and it is attached too and harmonized with my Celestron C8 SCT, for use in the Astronomical field. I do hope that you are not getting me mixed up those bloody dangerous idiots who both supply and use the above!!
It's time they banned aircraft from flying over areas where construction is taking place. A building has to stay up in the air for a hundred years, and these pontificating pilots want us to believe their needs are greater.
First time I've read this thread about l@ser pointers affecting air crew. In my past, I have studied astronomy and there is, rightly or wrongly, a growing trend amongst both amateur and professional astronomers to use l@ser pointers as an aid to point telescopes at targets in the sky and also to measure stability in the atmosphere.
Just thought it worth pointing out that they may not all be mindless thugs trying to bring us down but instead, unaware of the danger they are causing.
For what its worth, I'm doing my best to bring this danger to the attention of the astronomy community.
Location: ELLX (Someone else nabbed "The green heart of Europe")
Hmmmm.... My father used to be a hobbyist holographer twenty-plus years ago. He started out with a 5mW HeNe l@ser, at the time a tube slightly thicker than a kitchen paper tube roll, about three times as long. He then had a 25 mW HeNe l@ser which, as the 5 mW one, was in no way portable as connected to a mains PSU. This thing sat on his sand table encased in a rectangular aluminium housing, about 1.5 metres long.
I digress- How is it possible to shine a l@ser into an aircraft cockpit from below
How is it possible to accurately aim at the eyes of a pilot, given the width of a l@ser beam, the movement of the aircraft and, again, the fact that your l@ser wielder is surely on the ground, whereas the aircraft is in the air
Finally, a lot of cockpit glass I have seen is decidedly tinted (often veering towards the green?)- Whilst I appreciate there are many different wavelengths of coherent and non-coherent light, does this anti glare tinting (and anti-cosmic ray???) have no dissipating effect?