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Esteban
10-27-2007, 05:18 PM
Maybe there are more old.
Esteban
10-27-2007, 05:22 PM
Other. First constructional laser project?
Esteban
10-27-2007, 05:38 PM
Another early device.
Esteban
10-27-2007, 05:45 PM
Giant photos!
Esteban
10-27-2007, 05:51 PM
Tin cans detectable since 1937.
Esteban
10-27-2007, 05:57 PM
Many years we use the wrong tube???
Qiaozhi
10-27-2007, 06:05 PM
Other. First constructional laser project?
I prefer this one -> http://www.metacafe.com/w/756433 (http://www.metacafe.com/w/756433) :D
Max
10-27-2007, 07:18 PM
Other. First constructional laser project?

Hi Esteban,
this seems interesting for an extreme DIY project... can you post the full article (or send me by mail) ?

Kind regards,
Max
Esteban
10-28-2007, 03:23 AM
Hi Esteban,
this seems interesting for an extreme DIY project... can you post the full article (or send me by mail) ?

Kind regards,
Max

Hi

In wich email?

Regards

Esteban
Esteban
10-28-2007, 03:25 AM
I prefer this one -> http://www.metacafe.com/w/756433 (http://www.metacafe.com/w/756433) :D


Qiaozhi:

Sorry, can't access!!

Regards

Esteban
Elie
10-28-2007, 03:57 AM
I prefer this one -> http://www.metacafe.com/w/756433 (http://www.metacafe.com/w/756433) :D
DO NOT LOOK AT LASER WITH REMAINING EYE!
Seriously, this project is very dangerous. The laser pointers which are produced commercially are low power (although one should still not "get the beam in ones eye"), but what this guy shows will burn ones eye instantly. Lasers which are used in DVD players, etc., are high power devices, NOT TOYS.
Elie
10-28-2007, 04:07 AM
Esteban's source:
http://blog.modernmechanix.com/
Esteban is a bad boy!
Max
10-28-2007, 08:18 AM
Hi

In wich email?

Regards

Esteban

Hi,
my email is: snakeplissken2007@yahoo.com

Best regards,
Max
Max
10-28-2007, 08:29 AM
DO NOT LOOK AT LASER WITH REMAINING EYE!
Seriously, this project is very dangerous. The laser pointers which are produced commercially are low power (although one should still not "get the beam in ones eye"), but what this guy shows will burn ones eye instantly. Lasers which are used in DVD players, etc., are high power devices, NOT TOYS.

Hi,
yes that's true... 250mW laser could burn one retina in few time... probably less than 0.1 seconds... the focus inside the eye will burn the most sensitive central area of retina in maybe half that time with such power.

Laser pointers (toys and stuff for conferences etc) are much smaller powered maximum 5mW so 50times less than this bad project...often they are under 1mW real power.

Watching at them could give damages too... but cause of small power it requires more time to make real damages to retina... that's a live tissue and could also partially regenerate a very small burnt.

SO FOR PEOPLE THAT WANT PLAY WITH THEM ANYWAY: BE REALLY CARE ON WHAT YOU DO...

The same apply for DIY or repair or mod of DVD/CD/burners/readers ... DO NOT PLAY WITH THEM IF YOU DON'T KNOW ABOUT POWER AND DAMAGES THAT LASERS CAN MAKE TO YOUR EYES.

My interest in the old article is just academic... cause I know about everything about how it works but wanna see e.g. strategy for growing the crystal and similar stuff with just homemade stuff... could be funny see that thing coming from the year 1964!

Kind regards,
Max
Elie
10-28-2007, 08:35 AM
Come on, Max!
http://blog.modernmechanix.com/2006/05/01/build-your-own-laser/
Max
10-28-2007, 09:05 AM
Come on, Max!
http://blog.modernmechanix.com/2006/05/01/build-your-own-laser/

Hi Elie,
thanks for the link... now I see! :rolleyes:

That's interesting watching at a magazine of just nov 1964 and see a laser DIY project... about 4 years from first successful realization of a working laser source.

Best regards,
Max
Max
10-28-2007, 09:36 AM
Hi,
I've read it... but seems that the ruby wasn't homemade... just circuit and lamps... assembly was homemade diy project.

The magazine talk about "popular ruby size" 2 inches * 1/4 inch diameter ruby ...available... and also other kind of crystals for the infrared emission... but that means there were dealers of that stuff in the 60's in the US ??? :rolleyes:

I know that making synth ruby is not so difficault using right things... oven etc and some "ruby seed" for the crystal growing... but really wonder that in the US there was a market of amateur laser rubys in the 60's ! :lol:

Or maybe I don't understand well what's in the article ? Really puzzled now! :lol:

Kind regards,
Max
Qiaozhi
10-28-2007, 01:06 PM
Qiaozhi:

Sorry, can't access!!

Regards

Esteban
Seems to work ok for everyone else. Perhaps you need macromedia flash or something.
Qiaozhi
10-28-2007, 01:08 PM
DO NOT LOOK AT LASER WITH REMAINING EYE!
Seriously, this project is very dangerous. The laser pointers which are produced commercially are low power (although one should still not "get the beam in ones eye"), but what this guy shows will burn ones eye instantly. Lasers which are used in DVD players, etc., are high power devices, NOT TOYS.
Of course - do not look into the laser. Anyway, I never said it was a safe project. ;)
Esteban
10-28-2007, 02:59 PM
Esteban's source:
http://blog.modernmechanix.com/
Esteban is a bad boy!

Yes! You can subscribe to Modern Mechanix blog and receive every day on your email.
Esteban
10-28-2007, 03:01 PM
Seems to work ok for everyone else. Perhaps you need macromedia flash or something.

Qiaozhi,

Thanks very much. In one of my computers I can't, but in the other yes.

Regards

Esteban
Fred
10-31-2007, 11:12 PM
I think the real danger of the laser experiment is not tolook inside, as nobody would do that anyway,but accidental reflections on some surface.Even not very shiny surface can reflect part of the power back,it will be still too much for you eyes.
But the project is really cool! ;)
Regards,
Fred.
Elie
11-01-2007, 05:09 AM
Hi,
yes that's true... 250mW laser could burn one retina in few time... probably less than 0.1 seconds... the focus inside the eye will burn the most sensitive central area of retina in maybe half that time with such power.

Laser pointers (toys and stuff for conferences etc) are much smaller powered maximum 5mW so 50times less than this bad project...often they are under 1mW real power.

Watching at them could give damages too... but cause of small power it requires more time to make real damages to retina... that's a live tissue and could also partially regenerate a very small burnt.

Laser pointers are supposed to give you time to blink, before damaging your eye.
LASERS ARE NOT TOYS, AND YOU SHOULD NOT "PLAY" WITH ANY LASER, THIS APPLIES TO LOW POWER LASER POINTERS. IT IS POSSIBLE TO EXPERIMENT SAFELY WITH HIGHER POWER LASERS, BUT MAKING ONE INTO A LASER POINTER, AS THE GUY IN THE VIDEO DID, IS JUST PLAIN STUPID.
Elie
11-01-2007, 05:14 AM
I think the real danger of the laser experiment is not tolook inside, as nobody would do that anyway,but accidental reflections on some surface.Even not very shiny surface can reflect part of the power back,it will be still too much for you eyes.
But the project is really cool! ;)
Regards,
Fred.
No one would do that ON PURPOSE, but you know what happens with laser pointers. Also, as you point out, the fact that even REFLECTED light from this project can cause eye damage shows just how dangerous it is.