Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

Buy Site Supporter Role (remove some ads) | LPF Donations

Links below open in new window

FrozenGate by Avery

what makes a green emit IR?

Joined
Jun 7, 2007
Messages
1,771
Points
0
so why is it only green lasers that emit IR? do blue do it? and what makes the IR? why dont reds do it?
why do some green emit much more IR than others?

also, how can having an IR filter make the green any brighter? isnt it just gonna block the IR but not strengthen the green?
 





mikeeey said:
so why is it only green lasers that emit IR? do blue do it? and what makes the IR? why dont reds do it?
why do some green emit much more IR than others?

also, how can having an IR filter make the green any brighter? isnt it just gonna block the IR but not strengthen the green?
All Diode pumped solid state lasers that use crystals and an IR pump diode emit IR. Reds and blu-rays don't emit any IR because the laser diode already puts out the color that you want.

An example is my blue rpl. It has an IR diode in it putting out 2.5 Watts of IR and it puts out MUCH less blue light. Most of the wasted IR is turned into heat but some escapes from the crystals and exits the laser with the blue light that you want. The IR filter is placed after the collimator to catch any of the IR leaking out. 100mw+ of IR leakage is no good because it will kill your eyes. That is why all powerful Dpss lasers should have an IR filter.
 
interesting, so there is no green diode? its an IR diode converted to green? how can IR passing thru crystals turn it green?

also, i heard a blue laser uses rare crystals, but it also has a diode? so which is it?
 
mikeeey said:
interesting, so there is no green diode? its an IR diode converted to green? how can IR passing thru crystals turn it green?

also, i heard a blue laser uses rare crystals, but it also has a diode? so which is it?
In a typical 532nm green laser you have an 808nm IR diode pumping IR into the crystals. The first crystal lengthens the wavelength to 1064nm IR and the second crystal converts that into 532nm.
Go here for a detailed explanation of how green lasers work.
http://www.novalasers.com/articleslaserconstructioncomponents.html
 
mikeeey said:
interesting, so there is no green diode? its an IR diode converted to green? how can IR passing thru crystals turn it green?

also, i heard a blue laser uses rare crystals, but it also has a diode? so which is it?
I can't believe you're asking that question :o But anyway....DPSS means a diode is pumping a crystal(or set of crystals most of the times) to get what colour is desired.So they have both the diode and the crystals.
 
Switch said:
[quote author=mikeeey link=1208074705/0#3 date=1208229430]interesting, so there is no green diode? its an IR diode converted to green? how can IR passing thru crystals turn it green?

also, i heard a blue laser uses rare crystals, but it also has a diode? so which is it?
I can't believe you're asking that question :o But anyway....DPSS means a diode is pumping a crystal(or set of crystals most of the times) to get what colour is desired.So they have both the diode and the crystals.[/quote]

http://www.laserpointerforums.com/forums/YaBB.pl?virboard=b_general;num=1206843997  ;D I was thinking the same thing.  At least he has the balls to ask!  ;D

The title should more correctly read: "What makes IR emit green?" :P
 
Ace82 said:
[quote author=Switch link=1208074705/0#5 date=1208266924][quote author=mikeeey link=1208074705/0#3 date=1208229430]
;D I was thinking the same thing. At least he has the balls to ask! ;D
yep, its funny, when i get into something or learn about it, i may learn the advanced or hard things, but never covered the basic stuff.

for a while it was like that when i played guitar, i was able to play a fast challenging metal song, but not a basic song that should have been easier. that was cuz the basic song took a different technique (a much easier one too). So if i woulda just learned that to begin with...
 
mikeeey said:
[quote author=Ace82 link=1208074705/0#6 date=1208279129][quote author=Switch link=1208074705/0#5 date=1208266924][quote author=mikeeey link=1208074705/0#3 date=1208229430]
;D I was thinking the same thing.  At least he has the balls to ask!  ;D
yep, its funny, when i get into something or learn about it, i may learn the advanced or hard things, but never covered the basic stuff.

for a while it was like that when i played guitar, i was able to play a fast challenging metal song, but not a basic song that should have been easier. that was cuz the basic song took a different technique (a much easier one too). So if i woulda just learned that to begin with...[/quote]
Yea tell me about it, I can shred solos but mess up at changing basic chords :D Anyway, I think the DPSS process is more advanced technologicaly than soldering common components together, so you're fine ;D
 
It is not so difficult to make an homemade powerfull green dpss(178 mW peak power)...the total cost should be below 80$ if I remember well.
I bought the pump diode on ebay from a seller that is on this forum, "snoctony".
The crystals are sold glued togheter (or monolitic), so all the work is reduced to collimate the IR diode onto the crystal and align it to find the better output.
You can get the crystal used on ebay, or from another low power(so low cost) green laser.
The only problem is that your laser will be a bit ugly compared to a pen-style pointer ;D
 
Why did my 7.5mw greenie cost $1100 9 years ago. The 50 was over $10,000 in a module. Is it the crystals are so hard to make?
 
usakicksass said:
Why did my 7.5mw greenie cost $1100 9 years ago. The 50 was over $10,000 in a module. Is it the crystals are so hard to make?
It's hard to make the correct shape, coating and polishing of the crystal...but now the price is a strange things, it is under strange economy laws ;D :'( .
KTP is potassium tytanyl phosphate, nothing really expensive in terms of raw elements.
You can buy on ebay those horrible chinese green laser even at 15 $ and extract the crystals at very good price. These crystals (2 glued toghether really) are mounted on an heatsink, between the pump diode and the collimating lens.
 


Back
Top