Laser pointer choice and safety

[Tokolosh]

My dad works as a safety consultant/investigator for various chemical and shipping company's, in his job he often needs to point to things like stress fractures, load bearing points from considrable distance in full sunlight. Now i've been thinking about buying him a laser pointer for his birthday, but i have the following requirements;

Good visiblity of the dot at ranges 25 to 500m in full tropical sunlight (as far as possible without compromising the other requirments)
Absolute minimum of heat effects (Very very important safety feature) possibility of flammable gasses etc.
Very strong mechanical construction! Waterproof, Gas proof, Chemical resistance if possible are definate + points

I realise this is a demanding list, but which pointers come close.

 

[RobTheVIP]

I hope you have a lot of cash..I would imagine you would need at least 250 mW for it to be REALLY visible in daylight. As for minimum heat, at that distance I don't think it will be a problem. Wait for other replies as I am fairly new at lasers =)

 

[Xenodius]

No lasers that I know of are waterproof, however I don't think gases pose a problem. Chemicals would likely be VERY unfriendly to any laser you buy.

The only thing I can think of is if you bought a waterproof military-spec or higher flashlight and installed a laser in the housing, assuming it used some sort of rubber O-ring and not a glue seal like on watches.

As for power... I am probably not the best person to ask, however I know green pointers are brighter than reds per mW, however, as far as I know they are quite fragile in comparison since they are DPSS, unlike reds. Eye safety is probably one of the most pressing factors, since he is pointing things out to OTHER people! And presumably on metal, highly specular objects...


EDIT:
Distance is a large factor, I imagine that 250mW might be a little excessive, but I dunno. For a red, maybe not, greenie, oh yeah!

I think your best bet would be to buy a nice, ~100 or 150 mW greenie and find a way to put it in a military spec flashlight.

And wait for other peoples opinions! ;D

 

[Tokolosh]

As for power... I am probably not the best person to ask, however I know green pointers are brighter than reds per mW, however, as far as I know they are quite fragile in comparison since they are DPSS, unlike reds.  Eye safety is probably one of the most pressing factors, since he is pointing things out to OTHER people!  And presumably on metal, highly specular objects...

Yes eye safety is also important

EDIT:
Distance is a large factor, I imagine that 250mW might be a little excessive, but I dunno.  For a red, maybe not, greenie, oh yeah!

I think your best bet would be to buy a nice, ~100 or 150 mW greenie and find a way to put it in a military spec flashlight.

And wait for other peoples opinions!  ;D

i am willing compromise on distance, the eye and other safety features are much much more important!

 

[Tokolosh]

BUMP, come on who makes the best pointer for my needs? should i be looking at a red pointer???

 

[Xenodius]

I do not believe there is a pointer on the market that fits your needs... not as far as I know. But don't lose hope!

I will answer as good as I can considering that I am relatively new to this field...


First off, you probably want a greenie so that you can have a lower mW and still retain visibility.

Second, AFAIK you will need to do a lot of DIY work on this. Jetbeam makes a VERY small, above-military-spec flashlight for 40 bucks, however, nobody here has modded it yet, just some guy on YouTube. (100mW green) If you could put a second waterproof & flat lens on the front, you should be able to make a small, powerful, and extremely durable laser.

I read a review on a Jetbeam, and a guy said he rubbed it on a grinding wheel (not running) for 30 seconds, and it didn't even scratch the outer case, so they are built for a lifetime... one of the few things that actually ARE, and don't just say they are!

However, even if the flashlight is durable, if it gets dropped against a hard metal surface, it could knock the crystals out of alightment (IIRC) and 'die', or simply lose a ton of its output and also overheat faster.

I cant see you getting a full duty cycle on anything as portable as he likely needs, so keep that in mind too!

20 seconds on/10-15 seconds off is usually good.

PS: DealsExtreme sells a flashlight that looks exactly like Jetbeams AA model, is 10x cheaper, does NOT claim to be waterproof, and is a different color. (I thought they were Parkerized, don't know anymore ;D)

 

[pseudonomen137]

Sorry, but I gotta agree with Xeno. Even ignoring the saftey comment, the "full sunlight" kills it. I have a 300mW RPL green laser, and even that, in full sunlight, becomes faint and hard to see after a few feet of distance.

 

[Xenodius]

Sorry, but I gotta agree with Xeno. Even ignoring the saftey comment, the "full sunlight" kills it. I have a 300mW RPL green laser, and even that, in full sunlight, becomes faint and hard to see after a few feet of distance.

Just goes to show; I have no experience actually using high powered portables!

That is probably why they don't make a laser for that!