Advice needed for buget 200mw red's & goggles

[jacob0174]

So you believe they are providing enough protection? Also, a 100mw will melt it, from what I heard they can take a few seconds and its ok as long as you move the goggles around instead of just pointing it at in one area. If a 100mw will quickly melt it, how can it protect me from a 1-2 watt blue like they advertise? I hope you know that I really appreciate the help DrSid, :thanks:. (also, there are video's of people with 100mw lasers that burn through CD disks, so I will give it your 2000/time=mw test)

 

[DrSid]

It will give you several seconds protection, even few seconds at 1W .. but it will get damaged quite soon. I tested my goggles like this (true, with 1.5W 445nm) and I made a visible distortion right in the middle of the view field. I actually think it's a good test .. just use some corner of the lens.

 

[jacob0174]

Ok, then I will shine it for around 2 seconds in the corner where the frame blocks the veiw, and see how it holds up. I hope the reflection won't hit me in the eye, I'll use it below my waist angled downward.

 

[jacob0174]

So crazy news! Yesterday I took apart a dvd burner and found a diode that looked like a LPC815, but x16. So I went to radio shack and bought components to built an LM317 driver using this schematic.

The driver worked great! I got a steady 5.3 ohms, the desired number being 5 (+/- .5) ohms and attached some leads to connect to a 8.4v nimh battery. The voltage was regulated down to 2.8v as desired, and leads were successfully attached to the diode. Once we turned down the variable resistor to 0 ohms and let the normal resistors take over, the laser was completely unfocused, but outputted enough red to burn a little dip through a cd case at point blank with most of the red not on point. Since the diode looked like this.

It didn't seem to have a lens to focus it at all, is that part of the design of that particular diode. However, our poorest mistake was not putting the diode in an axiz module, and sadly, the diode overheated due to not having any heatsinking, and now outputs very little red. (I suspect an axiz module does some heatsinking, otherwise what makes it necessarily other than focusing, protection?) I may buy a PHR-805T in a module and turn up the ohms on the variable ohm resistor so it supply's 120mA instead of 250mA. Can someone tell me if not installing the diode in a module is what killed it, or was it the circuit. Everything on the multimeter seemed to be what we wanted, even though I couldn't measure mA, other things like ohm's, volts, and connectivity seemed correct. I just don't want to kill a $18 diode, I believe my driver works for 405nm.

 

[DrSid]

You will need some heatsinking even at these powers. But it could be anything really .. good job anyway .. that's how you learn things ..

 

[jacob0174]

Ok, I will buy a blu ray diode for the driver pressed into a module from hightechdealz <-- That one and get another old cd burner and press it in a module. Hopefully the only thing that went wrong was not having a module to heatsink. With a PHR803T diode, will axiz module heatsinking be sufficient for 120-125mA? Also, we will want to use this like it was a lab laser, it uses solid core wire, so I can bend it and aim it, but its stiff enough to not move. Do you think that aiming it at a black surface with goggles indoors, then taking them off to admire the dot/beam is acceptable? If not I can always use it outdoors. Thanks

EDIT: I ordered a PHR-805T since my goggles will protect me from 405nm. Plus an extra axiz so I can get a red diode too!

 

[jacob0174]

Also, just a heads up to people, at the local radioshack, the parts for the driver cost $15!!! Isn't the driver supposed to be cheap!?!? I think that's kinda crazy for a regulator and some resistors.

 

[DrSid]

Which reminds me about this cool thread about drivers ..

http://laserpointerforums.com/f67/how-laser-diode-drivers-work-explanatory-thread-71513.html

 

[Olao99]

Hey, has your 100mw red laser arrived?

How is it? Is it good?. I find $13 too cheap for a 100mw laser, so I'm eager to buy it.
Would you recommend it, does it pop baloons?