UKC

A new additional to my climbing bag, a cheap laser pointer. I found it very useful last night discussing a route and pointing at the holds. I wonder if others use one or if it's a "new" idea?

In reply to springfall2008:

I doubt there's an instructor in the country that doesn't have one.

In reply to springfall2008:

Very old idea welcome to the 20th Century

In reply to springfall2008:

Buy a 5.5W violet or UV laser from China, and remove grafitti, lichen, algae and polish...

...and your eyes...

(don't try this at home, kids...)

Yes, I meant 5.5 watt. These things scare the crap out of me.

In reply to captain paranoia:

'No Mr Bond, I expect you to die.'

In reply to springfall2008:

I know the issues with aircraft, but I reckon they could replace flares for rescue purposes, smaller, lighter, longer lasting.

In reply to captain paranoia:


Out of curiosity, if I were to do this - hypothetically - and pointed it at aircraft coming in to land at my local runway, would the pilots notice? Likewise for infra-red lasers, if such a thing exists

In reply to nufkin:

Infra-red lasers exist. It's what they use in laser cutters. You certainly wouldn't want to get in the way of one!

In reply to Hooo:

Infra red lasers are also used in CD / DVD players / ROMs and in fibre optic comms -so hardly novel.

In reply to nufkin:

The parent is prob talking about the lasers from wickedlasers.com and their 3.5w blue is very bright. Loads of vids on youtube.

In reply to Removed User:

Things like this:

http://m.banggood.com/2_5W-Desktop-DIY-Violet-Laser-Engraver-Engraving-Mach...

http://m.banggood.com/445nm-5_5W-5500mW-Blue-Laser-Module-With-Heatsink-For...

In reply to Hooo:


I suppose if they can cut metal the question is probably unnecessary, but if I looked into the beam of a UV or IR laser would my eye fry? Or would their being beyond our visible spectrum mean I'd be happily immune?

In reply to nufkin:


It depends on the power*. Just as it does with visible wavelength lasers. A 5.5W laser will burn the retina, assuming it's either a collimated laser beam, or focussed to a point. One problem with IR and UV is that they don't cause the iris to close, as a bright visible light would, which helps to protect the eye. High power white LEDs used in torches are UV laser diodes with a fluorescent cap, converting the UV into white light, also diffusing the power at the same time, so you need optics to form a torch beam. Not that the laser diode chips produce a collimated beam output anyway...

* strictly, the power density. If you start with a high power laser, but use optics to focus a collimated beam to a point, the beam will pass through the focal point and then diverge out the other side of the focal point, reducing the power density with square of the distance. Get far enough away, and the power density will be low enough not to cause damage.

In reply to springfall2008:
Very useful indoors for members of the Colourblind Climbers Club!!

In reply to althesin:


They already have

In reply to nufkin:


1) UV Laser - they'd not notice this immediately as glass is very opaque to UV radiation. If you could hold the laser spot on one small part of the aircraft for a while you might burn a small hole in the aircraft's skin and what ever is underneath, but a mount capable of tracking that well and fast is > £30k, and you'd need a targeting system as well.

2) Violet laser - yes, you can see violet lasers. Even 40 mW at 405 nm makes me exceptionally nervous compared to red/green at the same power. The fact people can but multi-watt lasers over the internet does not make me happy when I consider how dumb a few people are regularly being with other internet purchased items such as drones.

3) Infra red - yes, plenty of IR lasers out there. Unlike UV it would go through the glass so could damage their vision, 5.5 W is not good for the retina. 1/1000th of that power is not good for the retina. However as it's not visible the pilots wouldn't focus on it, so unless they were focused on infinity (instead of close instruments) that's mitigated somewhat. Probably not enough.

If the aircraft was a modern military jet, the pilot would probably notice their coherent radiation detector making a fuss. You might or might not have time to notice their response to this...

Lasers and aircraft. Don't do it.

In reply to nufkin:


The lens of the eye is opaque to UV - that means it absorbs it. So your vision bits (the retina etc) won't be subject to the light. But that absorption by the lens means heating, so enough power and it means burning.

Also, if you think of a UV or violet laser as a "cancer ray" you're on the right track. It's the same sort of wavelengths as the skin cancer causing components of sunlight, only a lot more intense...

Your retina can actually see UV light, and if you have your lens removed and replaced with an artificial one that is transparent to UV, you can too...

In reply to captain paranoia:


Rather amusingly we have signs up in the telephone exchanges at work that say 'caution, invisible laser radiation' and 'avoid exposure to beam'. How you avoid something invisible I don't know! The lasers in submarine cable equipment are pretty meaty, they'll carbonise any specks of dust on the connectors..

In reply to Removed User:

I honestly don't believe that site is legit, the power outputs are most likely bullshit. A 1mW laser is very bright, they really aren't selling 3.5w lasers!