Different internal components...?

As I understand it, green lasers use an 808nm IR diode to shine through grin lenses and two crystals which double the frequency of the beam to produce +/-532nm and then through an optical cavity and eventually to a collimator lens. HOWEVER, I have a green laser module which is composed of an open can diode with two tiny pieces of green glass in front of it (which in my limited knowledge I assume are the grin lenses) followed by a double concave lens and then the collimator lens. WHERE ARE THE CRYSTALS? What kind of module is this?

OPSL maybe? There are probably many different possibilities. It's beyond our knowledge and our budget at this point.

The crystals are the two pieces of "green glass". They appear green due to the thin film coatings on the faces that reduce reflections. GRIN lenses are just a specific type of lens that can be used to focus IR pump diodes, but in the case of most simple green lasers either the diode is directly coupled to the crystals (no lens used at all, the crystals are simply placed very close to the pump diode) or they use diodes that have FAC (a tiny piece of optical fiber attached directly in front of the diode) installed sometimes along with a convex focusing lens which focuses the pump energy into the crystals. In the case of your module, it sounds like your pump diode is directly coupled to the crystals.

ElektroFreak said:

The crystals are the two pieces of "green glass". They appear green due to the thin film coatings on the faces that reduce reflections. GRIN lenses are just a specific type of lens that can be used to focus IR pump diodes, but in the case of most simple green lasers either the diode is directly coupled to the crystals (no lens used at all, the crystals are simply placed very close to the pump diode) or they use diodes that have FAC (a tiny piece of optical fiber attached directly in front of the diode) installed sometimes along with a convex focusing lens which focuses the pump energy into the crystals. In the case of your module, it sounds like your pump diode is directly coupled to the crystals.

Click to expand...

haha i just decoded the binary code you have in your sig.. 'lasers are awesome'... classic

[/endthreadjack]

stuart

ok that is helpful. thank you.

How about this:
My brand new 2010 75mW Green pointer acts strangely. Sometimes when I turn it on the spot will change brightness and go very dim and then bright again and then maybe it will turn off altogether and not light up again until I take the batteries out and swap their positions (2 x AAA). Then it might turn on bright as ever and run for a while and then do it again or it might just do it as soon as the I push the button again. I have done a lot of reading on here and I figure it must be mode hopping. It seems to only do it when the batteries have been used a little and the beam shines straight and true so I doubt things would be out of alignment. I usually use Energizer rechargeables but it does it with alkalines too but it doesn't seem to happen as much. I owned a cheap but well built and very dependable 5 mW green laser for 7 years (the source of the above described module) that never did this. Could this be happening because of larger crystals (greater fluctuation in temp) or should I consider it defective? Maybe it's the batteries just crapping out from a large current draw? I really can't seem to put my finger on it.

If it doesn't happen as much with alkalines, then your problem is likely battery related. Rechargeables often do not provide as much voltage as alkalines, so in essence the laser thinks the batteries are dying. One thing you could try is putting a small folded piece of aluminum foil in the end cap between the battery contact and the case to fill any space between these connection points. Sometimes these connections just aren;t being made quite well enough.

lol that's kinda funny because i thought about doing that because together my rechargeables are about 1-1.5 mm shorter that duracell alkalines. i'll try it and see how it works out.

@ElektroFreak's sig.

01011001 01100101 01110011 00100000 01110100 01101000 01100101 01111001 00100000 01100001 01110010 01100101 00100001

Also, if the driverboard is just hanging out there, pushing the side button can cause it to flex and do the same thing that you describe. I can't suggest the best way to fix it, because I haven't even gotten around to fixing mine yet, but most people get some foam or cardboard, something that won't damage the circuit and isn't conductive, and cut it down to size to support the board.

You can check if this is your problem or not by applying varying pressure to the button and see if the laser responds in brightness.

well this is what i figured out: the tailcap threads are painted silver (its actually copper). the paint was interfering with the electrical connectivity. I used sandpaper and scuffed it so that copper was showing through and it seems to be working great now. However - it is definitely stuck it TEM:01 but this doesn't bother me because divergence is great and it appears nearly as bright as my brothers 150mW green pointer - at times it appears AS bright. It seems stable so I will not return it until it proves otherwise.

Thanks for your input.

crap well the driver broke or something because the button is stuck and it no longer works. i will be sending it back.