Green Lasers

[Sam Lee]

Anyone knows any contacts or places where they sell good and durable laser pointers ?
The one i have now seems to stop working. For some reason its fragile even when i handle it with care.
It is those that opens up into two in the middle to insert AAA batteries.

Would like to have one that is durable, 10mw or more that uses normal AA or AAA batteries.

BTW anyone have experiences with fragile laser pointers ?

[weixing]

Hi,

Anyone knows any contacts or places where they sell good and durable laser pointers ?
The one i have now seems to stop working. For some reason its fragile even when i handle it with care.
It is those that opens up into two in the middle to insert AAA batteries.

Would like to have one that is durable, 10mw or more that uses normal AA or AAA batteries.

BTW anyone have experiences with fragile laser pointers ?

OK... here I go again: It's my duty as a SingAstro moderator to inform you that it's illegal to own and use a > 5mW laser without a valid licence in Singapore. Any one found using class 3b & 4 lasers without licence in Singapore would be charged for violating the Act and could be fined up to maximum of not than $10,000 or imprisonment for a term of not exceeding 12 months or both.

Have a nice day.

[Sam Lee]

Thanks WX .
I hope we can still discuss the 'repair' topic here.

Anyone with suggestion can just PM me direct.

[Zephyrus]

Haha Sam, I doubt you can repair that laser. From the way you described it, it sounds like a low-quality china laser. As green lasers are DPSS (diode-pumped solid-state) lasers, the green light is generated in an indirect process since laser diodes are not commonly available in the wavelength range of green lasers. They have a crystal in the laser for the laser diode to pass through in order to produce the green light. Even an expensive laser, if dropped, would malfunction as the crystal would fall out of place and can no longer produce the 532nm wavelength.

In such cases, usually repair costs would cost much more than the cost of getting a new one. I've PMed you though, with regards to where to get a new laser. Also, for astronomy uses, the best kind of batteries would be the Energizer e2 Lithium as they can operate at extreme temperatures while alkaline batteries are decent in normal temperature range but not very well in low temperatures.

[gazza]

What about the APC (Auto power control) green lasers where they claim because of the power control circuit, it will last longer and not burn out the diode. Also can activate without having to rest in-between use.

These are usually more expensive than other ones I see. They claim to be made in US and have power close to 5mw and has a IR filter glass. Wonder if these are worth it. Thinking of getting one myself.

[Zephyrus]

Hi gazza, I don't see why anyone should pay more for these APC green lasers. There is no obvious advantage in the APC compared to normal lasers. The duty cycle of standard 5mW lasers are continuous (you don't have to rest in-between use), unlike the higher power ones. Also, on the power and IR-filter wise, it's almost the same as any other lasers. Nowadays, most china-made lasers are all installed with IR filters (you can check this by looking into the aperture of the laser, you should see a purple-coated lens). Therefore, a 5mW would not pose much of a threat unless shone intentionally into the eyes of someone for an extended period of time.

So bottomline is... unless these APC lasers are available at high power, don't get them. Since the main reason for the malfunction of green lasers are because of dropping (crystal dropping out of place from the impact) and not because of the burning out of the diode, the APC lasers does not overperform standard 5mW china-made lasers. The cost of the APC lasers are also much higher than the china ones, and it's not worth paying for it just for the diode to last maybe a few months longer. Most lasers have a lifetime, and maybe the APC are slightly longer, but optically, they do not outperform the other lasers. And china lasers perform just as good (or even better), and at a lower price. If it spoils in the year or two, you can even buy a new one after that.

[swat_pup6433]

haha eah.. talking abt green lasers.. my little pointer which exceeds the max allowed limit by a little.. seems to be taking the trashing quite well.. been dropped.. knocked.. even dropped into a puddle of water.. its still working like a jack rabbit!