Re: Cheep 1W 445nm laser diodes!
..., Tue Jun 15 2010, 07:03PM

If anyone needs these diodes, I have them for sale

They are amazing!

Re: Cheep 1W 445nm laser diodes!
IntraWinding, Tue Jun 15 2010, 08:17PM

Thanks for the heads up.

I'd like to understand how the 24 445nm diodes in each Casio projector are used, optically.

As a price guide, bear in mind if buying that this not for profit forum group buy
was charging £38 (US$56 today) per diode + AR coated lens

Unfortunately they don't seem to be selling them any more.

Re: Cheep 1W 445nm laser diodes!
Killa-X, Tue Jun 15 2010, 11:00PM



I own one, very cool :) The projectors run them around 600mA, and thers a lot of people running these at 1Amp...I've seen 1A runs for 40 mins on TEC systems. I, like most others, run them at 700mA I got mine for $50 after shipping, and recently $30


Same diodes are in these, I hope to get mine within 1-2 weeks!

Re: Cheep 1W 445nm laser diodes!
IntraWinding, Tue Jun 15 2010, 11:58PM


Where can I get one for $30?

Re: Cheep 1W 445nm laser diodes!
Killa-X, Wed Jun 16 2010, 12:06AM

They are usually $50 but there's some people at laser forums doing $30...You just got to prove your worthy of using them...

Re: Cheep 1W 445nm laser diodes!
Adam Munich, Wed Jun 16 2010, 12:08AM

I bought one of those WL arctic lasers. They use these diodes. I figured i'd just buy the ready-made laser because i'd have to machine a case for a diy laser anyway.

Re: Cheep 1W 445nm laser diodes!
Killa-X, Wed Jun 16 2010, 12:13AM


I manage to get mine for $196 with the 2 year warrenty :) I got in when it was free shipping, 10% off, and $20 warranty :D

WL claims its a TEM00 laser, but i highly doubt it. These are multimode diodes and make a ---- on your wall. It would be near impossible to get a TRUE TEM00 dot on the wall. And they claimed 1.5mm beam...Just got to wait and see!

Re: Cheep 1W 445nm laser diodes!
Adam Munich, Wed Jun 16 2010, 12:15AM

Eh, i don't care about TEM. I have a green laser that mode hops and it's quite interesting watching those patterns change when i put it through a lens.

Re: Cheep 1W 445nm laser diodes!
Killa-X, Wed Jun 16 2010, 12:21AM

Well, TEM00 is best for long distance pointing / beam. Else the distance you can see the beam at night is going to be short. Personal preferences. Where you get the 250mW green? O-Like? Rayfoss? My 200mW came from rayfoss :D

Re: Cheep 1W 445nm laser diodes!
Adam Munich, Wed Jun 16 2010, 12:27AM


I'm surprised you bought from rayfoss. They're lasers put out nearly half their power as IR. My laser starts at 350mw, then settles to 270mw over 3 minutes (green, not ir). It puts out alot of ir too. though.

I paid $570 8 months ago, and considering it survived multiple 10ft drops onto asphalt, i think i got my money's worth. ;)

Re: Cheep 1W 445nm laser diodes!
Killa-X, Wed Jun 16 2010, 12:34AM

Actually I tested mine to be 208mW :P Many others have found them to be at spec...I havnt had issues with them :) She even offered me a 600mw module for $300 to pretune my self, and they sell the full thing for $625. The module is everything but a battery and metal host. It has the lens, the driver, the 2W IR-pump, Good deal :D

Re: Cheep 1W 445nm laser diodes!
Adam Munich, Wed Jun 16 2010, 12:35AM

wow. i've had bad luck with rayfoss in the past. i'll have to take them off my avoid list.

Re: Cheep 1W 445nm laser diodes!
Conundrum, Wed Jun 16 2010, 07:25PM

just be careful guys, these things go from 5-10 mW to >250mW with as little as a 0.5mA power increase.
Its also possible that at sub threshold power levels they can be unstable and "burst" into dangerous laser output with no warning at all.

seems to be a known issue with blue diodes, as well as some newer high power reds.
Be careful! you don't get another set of eyeballs...

-A
#include "yes_LEDs_can_burn_retinas_too.h"

Re: Cheep 1W 445nm laser diodes!
IntraWinding, Wed Jun 16 2010, 07:54PM


Thanks - that's a useful warning

Re: Cheep 1W 445nm laser diodes!
Killa-X, Wed Jun 16 2010, 09:41PM

Its true. the threshold as stated is 200-300mA. Any lower and the laser is like 5-10mw. and as I slowly crank the diode, it hits the special number of my diode, and BAM! bright light. Then as I go up the brightness dramatically increases. Theres a ton of talk about these lasers. WL lends them to chance of cancer..Which isnt true.

These lasers are 345nm, and cancer can be given of UVB and UVC rays...UVA is top at 300nm...The raeson they link it to cancer probably is Blue light hazard. Dropping melatonin. But its still...Not really a risk.

These lasers do cut electrical tape like butter (VERY fast) at 500mA. I hit my figure during the cut as a test, yeah, pain :P

Also...I seen someone at photonlexicon claiming they are running a RGB projector, using these diodes at "1300mA" geehs.

Scroll down to the picture of the blue room, they mention these sleep disorders caused by blue LEDS, and possible cancer due to melatonin over long periods of times

Re: Cheep 1W 445nm laser diodes!
Adam Munich, Wed Jun 16 2010, 11:40PM

445nm killa.

Re: Cheep 1W 445nm laser diodes!
..., Thu Jun 17 2010, 02:30AM

They are run at 1.44A in the projector at a 30% duty cycle, I have on doing a burnin test at said 1.44A and so far after a day of burning I haven't been able to detect a drop in power (so it is within 0.5% of what it was this morning). Power output is about 2w depending on if you consider losses from the focusing lenses.

Re: Cheep 1W 445nm laser diodes!
Killa-X, Thu Jun 17 2010, 03:25AM


Typo :P

But 1.44mA at 100% duty? Must be using a TEC to run it at a stable temp. Surprise, if you are doing CW how much these can handle. It still makes you ask, Whats the max you can do on these? They really not cheap enough to just blow them off like the $7 20X red DVD burning sleds...

Re: Cheep 1W 445nm laser diodes!
..., Thu Jun 17 2010, 06:31AM

I am using a tec to keep the measurements consistent, but in the projector the diodes are cooled with a simple fan and run in the 40-60C range (I never tried letting it heat to the point where it shut down, but in normal operation the diodes are run quite toasty!)

I am trying to avoid running one to destruction, but my driver goes to 3A so expect some measurements taken up to that point before too long. I think my current plan is to do 24hr runs at 200mA increments (starting with a 1.4a run tomorrow) until the diode starts to show signs of distress.

Re: Cheep 1W 445nm laser diodes!
Killa-X, Thu Jun 17 2010, 07:50AM

should post a thing about your testing experiments at laser pointer forums...People would like to hear about your results if you do a plan to slowly increase. Do you have a true laser mW reader? If so a graph is nice too :D

Re: Cheep 1W 445nm laser diodes!
IntraWinding, Thu Jun 17 2010, 09:31AM


Can you post details of your test setup here?

Re: Cheep 1W 445nm laser diodes!
Kilham, Thu Jun 24 2010, 06:08PM

Posted a copy of some of the lost posts that were in my cache:

lpfthings
Posted: Tue Jun 22 2010, 07:28AM
IntraWinding wrote ...

LPF screwed up losing you!

What happened? If you let me know the banned nick, I can probably unban it for you if you'd like

I bought one of these diodes the other day, and now the flexmod laser drivers are out of stock for about a month! :(


Killa-X
Posted: Sat Jun 19 2010, 10:28PM
RickLaser, sorry didnt know you were talking about his IR engraver!
So the info below is for people who didnt know then!

I have no issues seeing a 5mw green laser IR dot through my laser glasses with my camera. I dont see any IR passing through the glasses from my 200mw violet or my 455nm running at 980mA. These lasers do not emit any IR. If it was a DPSS blue, it would...But these are diode based, not pumped.

Not sure if this is what you ment, but I'm just tossing it out for you that these do not emit IR. Its easy to see my 5mw green IR emmisions, but nothing come up for my blue, and my glasses are 200-540nm!

Here is my 445nm running 900mA into my glasses pointed at my hand. Nothing at all passes, my hand just glows orange because these glasses are designed to absorb and reflect light.

THESE ARE OD-4


RickLaser
Posted: Sat Jun 19 2010, 06:27PM
Conundrum wrote ...

interesting..

might be worth starting a new thread about homemade IR engraver setups, as the hazards are different to visible lasers.


A always use 808nm goggles, becareful with 808nm! It is at the edge of the visible spectrum and can fool you quite easily. It appears as a faint dim light even though it can be very intense in power. 808nm is in the retinal hazard zone


...
Posted: Sat Jun 19 2010, 06:02PM
I am using a pair of 'sand wind dust' googles that I got off ebay, they are relatively commonly available and meet mil spec MIL-PRF-31013 (note they come in 2 types, green lenses and brown lenses, the green ones do not block blue/green wavelengths but the brown ones do). I haven't measured the OD, but they block well enough that I feel safe around high amounts of 445nm light running around. I wouldn't trust them to save me from a shot to the eye however, if only because they would melt in short order!

The photodiode I just took a closer look and your are right the PHR-803T only has a huge multi-element array in it which would make it pretty unwieldy. I was thinking of the older CD-rom sleds which often had a separate power monitor photodiode which was quite large (probably 2mm on a side)
Conundrum
Posted: Sat Jun 19 2010, 04:22PM
interesting..

might be worth starting a new thread about homemade IR engraver setups, as the hazards are different to visible lasers.

-A


RickLaser
Posted: Sat Jun 19 2010, 02:48PM
Hi all,
i´m new at site, i work with Co2 lasers since 1983 , now i´m searching about laser diodes, i got a 2.4W 808nm module , it came with a C-mount diode and a positive meniscus lens, but the c-mount beam is not round but flat, with a mescus it gave me a 1.5mm spot, it can make a hole in a 3 1/2" disc drive and burn things, nothing usefull.... so i place a cylindrical lens between diode and meniscus, it give me a 0.4mm spot ( laser diodesarray is so hard to focusing..) so i rook the module in my laser machine with rubberbands..( don´t laught about...) well now it can cut some thin materias like paper, fabric, artificial leather..... i can´t compare it with my co2 lases but is a good start to undestand diodes... here a tube link to a video.


Conundrum
Posted: Sat Jun 19 2010, 01:37PM
yeah, that should work. Didn't realise the '803T had a built in photodiode but it should work.

re. attenuators, another idea could be to use two crossed polarisers with the angle adjusted to block most light.

the only issue here is that you might run into problems with them melting at this power level..

... what goggles are you using? i bought some off ebay for about £35 which are not ideal but have confirmed the OD to be at least 5 so they are safe for at least low power NUV and blue.

one of my friends also suggested mounting the whole setup in a light tight box, with an indirect viewing setup (mono video camera) and external red LED laser power indicator that can be seen through the goggles.

-A

"Bother" said Pooh, as England got pwned by Algeria...


...
Posted: Sat Jun 19 2010, 01:45AM
Using the detector out of a blueray sled (the PHR-803t specifically) is a great idea, I can draw up a calibration for one fairly easily. The only issue I see is that most photo diodes are very sensitive, and will saturate with more than 1-2mw of power, so some kind of standardized attenuator will probably be necessary, although it should be possible to calibrate your attenuator based on the detector from your drive.

On the bright side (haha) the diode I am testing seems to be holding steady at 1.5W (measured after a stock projector lens); the test has been running for just over 15 hours so far and the power just keeps increasing (presumably due to temperature variations in my garage). Link is same as in my previous post.
Conundrum
Posted: Fri Jun 18 2010, 07:15PM
Sam G (of RepairFAQ and LaserFAQ fame) suggested using a silicon solar cell as a sensor. the main problem with these is that they aren't optimised for blue light but as long as it is spread out over a large area of the cell the calibration should hold.

i've also found that the sensors built into PS3 BRIR diodes work very well indeed as they are already able to detect the 395-405nm light from the blue diode. Usually this sensor survives even if the diode is totally frazzled..

to use, find the appropriate pins and short all others to ground (including the IR) to prevent spurious photovoltaic output from the diodes from affecting the readings.

someone will need to draw a calibration table for these.

Obviously you will want to run it at well under its maximum power and/or use a known attenuation or the makeshift detector will not survive.


-A

#include "Never_overcurrent_tunnel_diodes.h"

Re: Cheep 1W 445nm laser diodes!
Kilham, Thu Jun 24 2010, 06:10PM

-and the post I made yesterday just before the forum died:

Has anyone measured the coherence length of one of these yet?.

Re: Cheep 1W 445nm laser diodes!
..., Fri Jun 25 2010, 12:29AM

It appears that at low currents there are some singlemode regions, where the coherent length is on the order of that of any other diode laser, see this blog for the details we have so far. I am going to be on vacation for the next week, but when I get back I plan to retrieve my spectrum measurement tools and provided I can find a usable set of mirrors for my coherent 240 confocal spec analizer (I think I have a pair for argon that will work, need to investigate) I should be able to get a measurement.

Re: Cheep 1W 445nm laser diodes!
Xplorer, Mon Aug 09 2010, 11:34AM

Here is a picture of the raw output from the multimode diode projected on a wall. 445nm is an amazing color but there is still a violet "haze" around the dot. It's not a pure blue like my 473nm DPSS lasers.




-Tony


[Edit: size]

Re: Cheep 1W 445nm laser diodes!
ConKbot of Doom, Mon Sept 20 2010, 04:02AM

I just recieved my wickedlasers "portable source" in, its definitely a beast. The collimation leaves much to be desired with quite a large spot. But with it focused to a smaller point its much more on par with what I'd expect from a 1W laser. With some more parts from thorlabs I hope to assemble a beam reducer and shrink the spot 4-6x, and hopefully maintain a decent divergence. I'll post more pictures once I get the optics assembled and mounted.


Is there anything solids or dyes thet can be pumped with 445nm for other laser experiments?

Re: Cheep 1W 445nm laser diodes!
Adam Munich, Mon Sept 20 2010, 04:14AM

The spot is large because these diodes have a massive fast axis. You'll need some cylinder lenses to fix the spot.

Re: Cheep 1W 445nm laser diodes!
Conundrum, Tue Sept 21 2010, 10:39PM

hm.. no wonder people are having trouble focussing them.

on the flip side, has anyone considered using one as part of a laser etching setup? at 1W it ought to make short work of most plastics and even ablate glass if black painted (!)

-A
"Bother" said Pooh, as he experienced the Vista boot fail...