Attn Kiwi Picaxers

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krypton_john

Senior Member
I noticed a couple of items at the Big Red Shed today that may be of interest:

- Outdoor solar garden lights for $2.95. It has a mushroom-like enclosure with a clear 360 degree window, rechargeable battery, bright wite LEDs, solar cell and presumably a light sensor of some sort, so should be good for opening up and transplanting in a picaxe brain of some sort.

- Keychain laser pointers for $2 complete with 3 button cells of some sort. Too small to enclose a pixaxe but the laser could be useful for something (gate obstruction detector, anyone? :0) )

Question - what kind of sensor would you detect such a laser beam with? Would you need to use any sort of signaling, modulation etc to filter spurious light?

Cheers,
JohnO
 
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westaust55

Moderator
Laser Pointers

In Australia there have been a number of incidents recently involving laser pointer beams being directed at pilots of aircraft and helicopters. I am aware of several reported in the news here in Perth and one last night in Brisbane.


Stupidity of use by an idiotic minority may lead to the banning of what is for most a useful tool.

The end result is that there are potential moves afoot to ban laser lights in Australia. As this is likely not just an Australian prank, the banning could become more widespread.
 
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krypton_john

Senior Member
Yes, it is a shame. However in this PC world we no longer punish people who do this sort of thing, and simply ban the misused item instead. Same for other stuff that is good fun but dangerous in idiot hands such as fireworks, howitzers etc.

I think it is absolutely inevitable that lasers will be banned eventually. It will take someone getting killed, but it will happen.
 
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demonicpicaxeguy

Senior Member
to make things worse it CASA investigators think that the recent freight plane crash may have been caused by somone with a green laser pointer

the banning of laser pointers aren't going to stop too many people because the laser diodes are in cd rom drives i think,
 
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manuka

Senior Member
Yes- I've just noted those Red Shed pointers as well, but they're identical to dollar shop offerings that have been on sale here in NZ for years.Ditto re solar garden lamps too- these regularly go in bulk ("8 for $20") at WH sales for just NZ $2.50 each.

Personally I too do NOT like lasers being so available. Aside from misuse (especially at sports fixtures) I've had any number of irritating exposures to them, with the most memorable being some kids in a car ahead of me firing away out the rear window at night. I never managed to pass & shake my fist & just eventually pulled over & waited.

Both offerings are electronic indeed goldmines,although I NEVER bring out anything laser pointer orientated out for kids to ponder... Stan (Wellington,NZ)
 
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BrendanP

Senior Member
On a similar note Stan the federal gov. is going to prohibit the sale of some types of lasers in Australia because of cretins pointing them into the cockpit area of aircraft landing and taking off.

(I just reread the thread and saw this has already been mentioned.... Blame it on the bourbon.)
 
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Dippy

Moderator
I agree lasers and idiots are a dangerous mix.
If I'd been Stan I'd have taken the car number/licence plate and reported it to the police. Or rammed the car and punched Dad on the nose.

These little/cheap pointers shouldn't be allowed on general sale... but then if you support 'low cost' Chinese products you've only got yourselves to blame. It's not the product, it's who uses it.

I thought lasers in CD/DVD players were lensed for very short focus?? Obv they could be fiddled with I guess even if that were the case.

With Brendan on the bourbon I wouldn't have thought he could hold it steady enough to blind anyone.
Can you imagine how steady you'd have to be to get someone in the eye at 300 metres?

As we have just had a boring lunch break today I got a (sober) colleague to wave a 1mW red laser at me at about 100 metres. In 5 minutes I saw it flash once, the rest of the time the beam was elsewhere.... and so was my belief in people being blinded by cheap pointers at distance.
Though I wouldn't disagree with the dazzling effects of especially blue-green lasers at night.

You could set one up to 'blind' surveillance cameras if you wanted.

"PC world" (free ad) , yes , but don't forget the 'compensation culture' too! A school bus driver was 'permanently' blinded by some kiddy shining one in the rear view mirror for 0.1 seconds. I bet he wasn't blind enough to read the compensation cheque 2 months later!!

But to answer an earlier question about sensing; any un-filtered photo-diode can detect the laser. Even an LDR. Filtering will make it better obv. For a red laser use a red filter. Not really rocket-science. If you want to see the laser for yourself then wave it down the garden with a ruby-red clear filter in your pork-pie. Choose the filter to suit the laser wavelength. And yes they can be modulated. They are only modified LEDs.
Beware of IR laser wavelengths though , they tend to be shorter than LED and more care is required for efficient filtering. And also note that just cos you can't see an IR laser it doesn't mean it's not potentially hazardous.
 
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