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

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Diodes under scanning conditions test fund

Joined
Apr 28, 2008
Messages
2,235
Points
0
A lot of people on the forums stress test diodes for use in pointers and how high they can be pushed, but if you're like me then you're more interested to see how the diodes cope with modulation and extended on time.

I don't have the equipment to do any tests personally, but IgorT (who is testing the 8X diodes at the moment) has offered to test the diodes with FlexMods through various stress testing.

I don't think we have enough people interested in scanners for a 8X test (we'd need around $160 for that) but we could stress test a 6X diode or two to death to see what is a safe amount to set those diodes to.

This is just a feeler at the moment, just to see if there are enough people out there interested in this kind of test. Just post and say how much you'd be willing to donate to this test (need about $50), if there's enough people then we can move onto the next step :)
 





Joined
May 24, 2007
Messages
3,394
Points
0
saving your money im just about to put some 6x diodes into two scanners
 
Joined
Apr 28, 2008
Messages
2,235
Points
0
Okay, that's great! What powers are you planning to run the diodes at?

I still wouldn't mind running a diode to the death though... for all we know this diodes could be like the PHRs and will take much more punishment than expected.
 
Joined
May 24, 2007
Messages
3,394
Points
0
215mw each

ive gto two seperate projects each using 6x 405nm diodes
 
Joined
Apr 28, 2008
Messages
2,235
Points
0
215mW is quite a bit, are you using a 405G1 lens for extra power?

How long do you plan to leave the scanner on at a time, are these diodes set for indefinite use?

Would the analogue modulation and switching the diode on and off all the time affect the life of it too badly?
 
Joined
Apr 29, 2008
Messages
1,562
Points
48
switching the diode on and off all the time affect the life of it too badly?
I would think that as a good thing, as these diodes are designed for pulse use anyway, and it reduces the total time that the diode is actually powered on. (less heat)
 
Joined
Nov 7, 2008
Messages
5,725
Points
0
215mW is quite a bit, are you using a 405G1 lens for extra power?

How long do you plan to leave the scanner on at a time, are these diodes set for indefinite use?

Would the analogue modulation and switching the diode on and off all the time affect the life of it too badly?


The general consensus is that laser diodes prefer being pulsed, as long as the current never exceeds the maximum rated current. Past the maximum rated current, who know what will happen.. The nice thing is, the pulsed current rating is quite often substantially higher than the CW rating, but the pulse widths have strict ratings as well. With widely varying pulse widths as found in laser projectors, some middle ground between the max pulse and max CW current is likely the sweet spot. Very touchy at high current, though.
 
Last edited:
Joined
Apr 28, 2008
Messages
2,235
Points
0
Okay, that makes sense then. So I guess we can essentially drive the diodes to the same amount as we use in the pointers, with adequate heatsinking of course.
 
Joined
May 24, 2007
Messages
3,394
Points
0
215mW is quite a bit, are you using a 405G1 lens for extra power?

How long do you plan to leave the scanner on at a time, are these diodes set for indefinite use?

Would the analogue modulation and switching the diode on and off all the time affect the life of it too badly?

as stated above really.

the diodes will be under modulation so the use will be alot less than CW use.

at the moment i only have standard aixiz lens but do plan on getting some decent lens.
 
Last edited:
Joined
Jul 27, 2007
Messages
3,642
Points
63
I used a PHR in my scanner for a little bit at 110mA, it died randomly one day :(
 
Joined
May 24, 2007
Messages
3,394
Points
0
I used a PHR in my scanner for a little bit at 110mA, it died randomly one day :(

could of been a million reasons it died LOL

mine are fully insulated so the only reason they will pop will be from being over powered.
 

IgorT

0
Joined
Oct 24, 2007
Messages
4,177
Points
0
With widely varying pulse widths as found in laser projectors, some middle ground between the max pulse and max CW current is likely the sweet spot.

I would have to agree..

SightFx already contacted me about GGW testing in one of his kits, and i recommended 150-160mW (after plastic lens) for some level of "reliability", if it's to be used in a hobby scanner.

While GGWs can be reliable enough as hobby laser pointers at around 200mW, in a scanner hours can pile up rapidly, depending on the type of use.. In any case, definitelly MUCH faster than in a pointer..

But then again, GGWs are relativelly cheap so it's not a biggie if they die rapidly i guess... Unless you actually need reliability like for professional laser shows, where it's not much fun if one pops in the middle of a performance.
 
Last edited:




Top