I tried to buy a high power 532nm green laser from China a few years ago through Aliexpress.com and found that most of the listings for high power laser pointers on that site are lies, claiming their units can do 10 times more power than they really can. Then I started to research and found my expectations were way out of line for the money, as well as for the kind of power they advertised to be possible in a pointer laser.
I still want a high power pointer, the next time I buy one, it will have one of these modules in it:
1.3W 520nm Laser Diode in Copper Module w x Drive G 2 Glass Lens NDG7475 | eBay (Note from seller: 120 seconds on 30 seconds off with proper heatsinking).
Or, from the same seller but for less cost here:
https://sites.google.com/site/dtrlpf/home/diodes/ndg-1w-520nm
The above module is only 12mm diameter, maybe 30mm long, or very roughly 1/2 X 1 inch
This unit isn't 532nm or DPSS, it is a 520nm solid state green laser diode and won't have as tight a divergence as a DPSS 532nm green laser (not a fair statement though, nearly all DPSS lasers have beam expanders built into them), but it's close enough for my needs, especially when I can use a beam expander to reduce the divergence far below that of a 532nm laser, if I want.
If you buy one of these you will need a heat sink to slip it into or it will get too hot and destroy your diode. There are several members here who can make laser pointer hosts for these, or already have suitable hosts for sale off their shelf to pop one of these into. If I were to have a host made for one of these, I'd have one with a big enough heat sink to allow at least 10 minutes of operation before it gets too hot, if it can be done. Would I stand outside for ten minutes straight with it on pointing into the night sky viewing the awesomeness of it? No, but I could come close to that
or use it for five minutes and then want to do it again without waiting for the laser to cool down each time, so a BIG heatsink is a MUST for me.
I've been tempted to buy a couple of ready to go hosts on impulse here a time or two, but the damn heat sinks are often too small for what I want, or no finning to help take the heat away faster. I like massive deep heat sink fins! This 1 watt output diode will produce a lot of heat, so a host with a wimpy heat sink just won't cut it for me. If you do get one, make sure the head has DEEP heat sink fins and is big enough or the duty cycle will be fairly short before it gets too hot.
Of course, a massive solid block of aluminum or copper will soak up a lot of heat and can allow a good amount of operation time before it can get hot enough to cause problems for the diode, but the same block with deep fins is much harder to heat up as well as much quicker to cool down, extending the duty cycle or operating time of the pointer quite a bit more, so unless necessary, I wouldn't have a heat sink without fins.
After having dissed some of the wimpy heat sinks on laser pointers I've seen offered ready to go here, most people don't have 1 watt pointers, so they don't need the larger heat exchanger fins on their pointers I am looking for, but even then, I'd want some heat sink fins on a 100mw laser pointer too, regardless. You can have a custom host built to your liking too, there are machinists here with superb skills to build just about anything you can think of, but be ready to pay ahead of time for them to begin work. Some of their prices are quite inexpensive for what they do.
