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BlueWolf
5th Mar 2006, 09:46
I bought two of these gizmos today. I was only going to get one, but they were only $2 at the Warehouse - about 80p in Pomgolian money - so I bought two.

I have a legitimate purpose; I want to use the device to check for Tindall Effect in my colloidal silver.

There's a warning on the pack as to not pointing in people's eyes, and a disclaimer saying they should be kept out of reach of the under 12s; but no restrictions on their sale, and only $2 each!?

We had a bit of fun this evening, watching Medium Cat and SWH chase the laser dot around the floor. After dark, I went out to check the range of the thing, with a possible view to fitting one of them on one of my rifles for night shooting. It clearly illuminates the neighbour's barn some 250 yards away, and lights up the road sign on the corner 100 yards distant like a flashing light on a Police car. All this from a thing two inches long and 3/8 thick, powered by three camera batteries. It's half the size of a pen, and you can buy it for two bucks, and it has that sort of range?!

I presume it's similar to the sort of device being used by little :mad: to blind pilots on approach. On the one hand, I marvel that in the space of three-quarters of my lifetime, lasers have gone from being the stuff of foreign science, huge, unobtainable, and massively expensive, to the kind of thing I have described; on the other, shouldn't there be some restriction on their sale?

BlueDiamond
5th Mar 2006, 10:18
You have to be terribly careful with those things, Wolfie, as you are aware. There have been instances of permanent eye damage being caused, usually by kids playing with them ... they should definitely not be left withing reach of children! I have one myself which was given to me years ago, the beam can be changed from a - to a . to either point out or underline what you are looking at. They do have a remarkable range though.

MagnusP
5th Mar 2006, 11:05
It's half the size of a pen, and you can buy it for two bucks, and it has that sort of range?!
Well, as someone working in astronomy, I'm fairly relieved to know light has a range of more than a few metres. ;) But I know what you mean.

corky83
5th Mar 2006, 12:50
Was the advert for blue laser pointers at the bottom of this thread coincidental? (Or does everyone get different adverts? I don't know how these things work...)
Working in the optics industry, I get so see lots of different types of laser - ranging from the handheld to those the size of warhouses. The general advice is that class 1 or 2 lasers may be used unsupervised with little risk. Class 1 lasers are thought to be below the threshold for eye damage and exposure to a class 2 laser will activate the blink reflex, preventing injury. Your laser pointer should fall into one of these categories. Neither class will cause skin damage.
With this in mind, the acutal health effects of laser pointers (providing they are in one of these classes) are minimal and it is therefore hard to impose controls on who can/can't use them. Of course, the distraction of having any bright light shine into your eyes is another factor, and one which I am not qualified to discuss.
You can find some good information on laser safety from the UK Health Protection Agency here:http://www.hpa.org.uk/radiation/understand/information_sheets/laser_pointers.htm. Obviously reading this is no substitute for proper laser saftey training.

tall and tasty
5th Mar 2006, 13:23
yheu are brillant in lectures and as a tool for pointers in demonstrations . But as Bluey has said very very dangerous with children and if they get near your eyes.

They will be taken off you if you travel on airlines too.

TnT

ps but using them to tease the kitty, I used to with mine hours of endless fun there :}

tony draper
5th Mar 2006, 13:44
Good for strapping on yer rifle as well,they don't like the red dot on em.:E

Avtrician
5th Mar 2006, 13:56
My son bought one of those things in Phuket a few years ago, ( pre tsunami) and just to see how good ity was I aimed it at a hotel (multi story thing) (about a Kilometer away) from our hotel room balcony. I was expecting maybe to see a faint small dot, well i was wrong, I saw quite a bright dot on the wall, the whole wall. Yes the whole side of the hotel ha a huge red circle on it not jus a red dot. I wonder if anyone in there ondered why their room was a bit red inside???.

Just as well it couldnt focus tightly, probly would have blown a hole thru the place:E:O

BlueWolf
6th Mar 2006, 06:29
Well, I went and cleaned the shop out of its remaining stock this afternoon, all $8 worth of it. On the one hand, with batteries included in the pack, it's a cheap way of buying batteries, and on the other, I'm performing a social service by keeping them out of the reach of children.
:hmm:

Echo Zulu Yankee
6th Mar 2006, 12:41
Looking at the link on the bottom of the page, it says their "Spyder" product has a range of up to 120 MILES!........ HOW!? What possible use would this be!?

EzY