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FrozenGate by Avery

Help needed for a noob (me)

J

Jack Frost

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Feb 21, 2018
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Greetings!

At a recent family gathering I mentioned I was becoming fascinated with laser pointers and lasers in general. An overzealous but well-meaning relative purchased for me a very powerful laser with all the accessories:

Sanwu Spiker, 445 nm, 7000mW, multimode, G7 lens, lasersaber attachment, tripod, and X3 Beam Expander. Oh, and safety goggles from Sanwu. This worried me so I got a pair made for medical laser technicians. Are the Sanwu goggles sufficient?

I am overwhelmed and I do not want to A) burn down my house, B) cut my cat in half, or C) go blind. What is a noob to do? I’ve burned some paper, played with the saber, and shined the laser up and down the street at night. I’ve used it mostly on low or medium power because, wow, that is one bright light. I understand the basic safety instructions (don’t look into the laser; don’t put any body parts in front of the laser; don’t shine it at planes, cars, cats, people, reflective surfaces, etc.; remember the duty cycle; and so on) but I can’t really show it to others as I only have one pair of goggles and I don’t want anyone to get injured. I guess I’m looking for tips and other fun/interesting things to do. Can un-goggled people indoors look at the patterns created by the pattern caps? I would think no, but if possible at what distance? Should I try to burn through a brown beer bottle? (That looked very cool in posted pictures.) Sear a hot dog or other food items? Carve my name in wood?

After that brief phase I'd like to start learning useful stuff; the scientific principles involved, proper uses for this technology, optics, and possibly learning to build my own unit.

I would appreciate any useful information you could pass along to this noob.

AdTHANKSvance,

Jack
 
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Welcome Jack,
First, please make a post in the welcome section with a little about yourself.

As you seem to know, a 7W laser is very dangerous and you and anyone watching should always wear goggles, unless shining into the sky. Even diffuse reflections are dangerous, so I would recommend not using the pattern caps inside.

I would not trust the Sanwu goggles, not with a 7W. Read up on safety, there are some useful threads in the “laser safety info” section. Here’s what can happen if you don’t use proper safety precautions, and this was with a 1W, not 7.
https://laserpointerforums.com/f53/hit-eye-1000mw-445nm-blue-laser-69469.html

Stay safe, and have fun
 
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Welcome to the forum, first post should go in the welcome section introducing yourself, but this is sort of an introduction the way you wrote it too. You appear to have done a lot of reading already, I'm surprised you are asking the OD question with the knowledge you already have

Here's a screen shot I ripped from another web site showing the percentage of reduction for various OD laser glasses or goggles:



Most consider under 1 milliwatt through the glasses and into the eye to be safe enough for a direct hit, but don't do it on purpose, if focused to a tiny spot on the back of your eye, even that amount of power is bad news.
 
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I've done it with a NUBM44, stings and does so quickly, not a bright idea.
 
I don't get any part of my anatomy in front of a 1 watt or higher power laser. It is not a great idea. I remember getting some beam shots of my 1350 mW 532 DPSS laser and passing in front of the beam quickly it burned very painfully. Now, the divergence of this laser is better than any direct diode multi-mode lasers, but the closer you get to the beam the more it's going to hurt.
 
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Pain from direct exposure = poor mans laser power meter, calibration correction factor; skin color x time x how loud you scream.
 
Thank you all for your replies. You've given me a lot more to read about! I've also posted an introduction about myself in the welcome section.
 
Humm, what do I do with mine mostly? Cut those pesky mayflies in half! :gun: (crane flies for you other people).
 
Being burnt by a laser is like having someone stick a hot needle into you. A very sharp burn. Not wise to purposely allow yourself to get burnt. ;)
 
If you want to avoid feeling like a hornet has stung you, don't let a 700 mw 405 nm laser hit your skin, they are the worst. My experience with a 6.5 watt 455 nm NUBM44 was a very brief clip on my hand, that too burns like the dickens, but it wasn't on me long enough to get a mark I could see.
 
BDR-209's burn like hell. They have excellent beam specs and coupled with the power and wavelength, they burn pretty much anything.
 
405 nm is very high energy as is any blue wavelength. The shorter the wavelength, it really packs it in. You can think of it this way, if you look at the waveform from a long wavelength, the sign wave is spread or streatched way out, but for a short wavelength they are bunched together tightly and have a greater number of up and down transitions in a space of time which means more lively energy is packed into it, zap!
 
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The shorter wavelength allows a tighter gaussian beam. But it's mainly due to the absorption at that wavelength as well.
The higher photonic energy does allow more energy to be transferred by each photon making it slightly more efficient for heating objects up, but no gain in overall power. The intensity however does make a huge difference.
 
Yea, I just edited my post before I saw your response to make it more accurate, those quick transitions sure do the job of affecting materials with the shorter wavelength. This was the start of a new era of physics, when the way different wavelengths affected the release of electrons from a black body differently was observed, they called it the Ultraviolet catastrophe and from that, the eventual birth of quantum physics.
 
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