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Laser Pointer temp.

1337mW

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Nov 10, 2006
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I notice that my 15mW laser performs quite poorly in the cold. Sometimes if I keep it on for 45 seconds or so, it begins to warm up and the brightness is better. I'm curious as to what makes the laser perform this way. How does the cold make the laser weaker? Just curious :cool:
 





NairB

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Nov 3, 2006
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I believe the temperature may have an affect on the diode wavelength so that its slightly off. Instead of the diode outputting 808nm it may be 809 or 807 etc causing the crystals not to lase at their desired wavelength.

There is a name for this particular symptom and I can't remember what its called :-/
 
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Nov 11, 2006
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All diodes are temperature tunable, so as Nair pointed out, an 808nm diode may operate at 808nm optimally at roomtemp, but as the temperature is increased/decreased, the diode will output 808nm (+) (-). This means the MCA isn't lasing at the optimium 808nm, so overall ouput is decreased.
 
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1337mW said:
I notice that my 15mW laser performs quite poorly in the cold. Sometimes if I keep it on for 45 seconds or so, it begins to warm up and the brightness is better. I'm curious as to what makes the laser perform this way. How does the cold make the laser weaker? Just curious :cool:

Mine does that too... I have a 135mw
 
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Nov 8, 2006
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i would think heat would be an issue with lasers (well, i know that it IS an issue) but i never thought regular cold would affect a laser adversely... i could be wrong, but as far as i can tell, my lasers work BETTER in the cold, and the only temperature that i know my laser doesn't work at is –273.15 °C.
 
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These things are so critical in thier alignment... ever tried shooting a laser across only 3 mirrors?
Cold moves things as well as heat. Both affect efficiency of componets too.

I think some lasers must be slighty misaligned and heat actually brings them in line, but then too much adversly affect it in other ways that affect all lasers and overclouds the benifits of perfect alignment.

I know almost nothing about lasers, but this is just my guess, maybe I'm totally wrong, maybe I'm only partly right, maybe I'm perfect! LOL!

But some do respond positively to being warmed up.. Mostly bench units, but others are opposite.
Mine peaks of a couple of seconds and then drops "this is normal" but then over the next 15 - 30 seconds it actually gets stronger again approaching its peak wattage and stays there.
I never let it get hot enough to start falling due to heat by leaving it on too long..... 30 seconds is about my max for my pen. At least thats all I do.
 

NairB

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Hey Windstrings, thats good you dutycycle your laser at 30 seconds. By doing so, you are prolonging the life of your laser...so good for you, very wise ;)
 
Joined
Dec 30, 2006
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So far I have had absolutely no need to leave it on longer than that.. why not give a breather?

I'm getting ready to get my 175 W Aries that I can leave on constantly.. I bet I still won't go over 30 seconds!! LOL!

I'm excited in deed!... this will peak at over 225 and remain constant at 193 with a 0.9 divergence..... that much power "true constant power" with that tight of a beam is bright even in a fully lit room.

I got it right before the sale dissappeared.. I believe they now have their 100, 125, and 150's on sale.
If they still have it, they have a 150 thats runs a constant 173 or so... not bad....

http://www.laserglow.com/handheld.html
 




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