Another Dead Laser - Warning Thread Contains Swearing!

[dsli_jon]

Hey Chris -

Ah.... YES.... SML in rochester for near 10 years. And you are????

Ha! Yeah, I guess the 'Location: San Salvador...' part might throw you off a bit I'll PM-you so we can get off this line...

...sorry, Jem!!
peace...
j

[skacutter]

Welcome to PhotonLexicon, Chris. I see you are in New York. There are a few members in your area that might be able to offer their assistance with your problem. Unfortunately, it's going to require some do-it-yourself work. (See below)

About how long ago was the initial purchase? Do you remember? Also, when did you first send it back? Dates can be important, because as you'll see below, you are but one victim among many. Any information you have will be another piece to the puzzle.

Maxyz modules have supported analog modulation for several years now. If yours was a TTL-only model, you may have purchased an older, possibly used unit. Do you remember the name of the E-bay seller you bought it from? And was it listed as a new unit?

As for the failure mode - the most likely cause is back-reflection, not a driver failure. Backreflection causes instantaneous (and permanent) damage to the diode face. Most Maxyz modules failed because of this, mainly because they were operated very close to their absolute power limit. That makes them more suceptible to damage due to back-reflection. For a while, you could get them repaired at cost, even if it was back-reflection that killed it. But lately that option has vanished.

The "David" that we are talking about in this thread is David Wu, of Lasever products in China. This thread doesn't have anything to do with the Maxyz modules, but rather the Lasever DPSS units (especially the 473 nm blue ones) that developed power output problems after a few months use. However, there are plenty of other threads devoted to the Maxyz modules.

The guy that makes the Maxyz modules is Chuck Barber. He is registered here on PhotonLexicon as "Marconi". Also, his girlfriend (Maxine) is registered here as "K-car". Maxine used to help Chuck with the sales of his Maxyz modules. (That's where the "Max" in Maxyz module comes from.) My guess is that the girl you dealt with was probably Maxine, and yes, they both had E-bay accounts and sold an awful lot of Maxyz modules through E-bay.

Maxine was handling *all* the shipping for Maxyz modules from late last year (2007) until the early part of 2008. However, around that same time the complaints started piling up about Chuck. People weren't getting their diodes, and Chuck wasn't answering e-mails or phone calls. Granted, he had back surgery during that time period, so some people were willing to give him the benefit of the doubt. But the complaints kept comming.

Since then it's gotten much worse. There are a number of members here that did not receive their lasers. Some people were owed warranty repairs, while others had paid in advance for new lasers and never received them. Still others sent equipment to Chuck to be modified and never heard from him again. Some of these deals that went bad ended up costing the members thousands of dollars.

The last time I talked with Chuck was in May or early June of 2008. Since then I haven't spoken with him or received any e-mails from him, and I don't know of anyone else that has spoken with him either. I think he's avoiding the forums. That sucks for his former customers, but there's not much else we can do at this point.

Search for "Chuck" and "Maxyz" and you'll find plenty of threads explaining all the above in much greater detail.

If the problem was caused by back-reflection, there is no fix other than to replace the laser diode. If you are comfortable doing the work yourself, you can replace it. There was a discussion recently about the inner components found in a Maxyz module, and the consensus was that there isn't anything special to be found.

Adam

PS: Be sure to fill in your profile; that way you don't have to always post your location at the end of your messages. Also, it will make it easier for folks in your area to see that you're local to them. With any luck, one of them might be able to help you get a replacement for your dead Maxyz module.

Q:About how long ago was the initial purchase? Do you remember? Also, when did you first send it back? Dates can be important, because as you'll see below, you are but one victim among many. Any information you have will be another piece to the puzzle.
A: I bought in late 2006 and sent the unit back maybe 2 weeks later.


Q:
As for the failure mode - the most likely cause is back-reflection, not a driver failure. Backreflection causes instantaneous (and permanent) damage to the diode face. Most Maxyz modules failed because of this, mainly because they were operated very close to their absolute power limit. That makes them more suceptible to damage due to back-reflection. For a while, you could get them repaired at cost, even if it was back-reflection that killed it. But lately that option has vanished.

A: I do not belive my failure mode could have anything to do with back- reflection (AKA Backscatter). The unit was operated on my test bench and the beam was terminated on a black aluminum surface. After the failure the unit still outputs 1mw with the beam looking exactly like it did at full power (Crosshair pattern common to this unit). It really does seem like TTL control failure or PSU failure


Q: Or rather "Comment:"
Since then it's gotten much worse. There are a number of members here that did not receive their lasers. Some people were owed warranty repairs, while others had paid in advance for new lasers and never received them. Still others sent equipment to Chuck to be modified and never heard from him again. Some of these deals that went bad ended up costing the members thousands of dollars.

A: OK I was a bit confused by your first email thinking that MAXyz was in good standing on this site. I am following the correct thread and I also last heard from chuck via ebay in May 08 via ebay. He seemed very willing to help and asked me what my serial number was. It was after responding to him with the details that I never heard back. So sad because I need that darn 660 to complete my RGB projector

Skacutter..... Admin www.kasperwing.com

[buffo]

This is the first I have heard of back reflection.

There's some good information in Sam's Laser FAQ about it. Look in the diode laser section. There are also more than a few posts that address it here.

I have heard horror stories about reds dying all the time. Mine is shining away happily. Am I just lucky?

Possibly. Or maybe you've never reflected the beam back into the diode. (which might be considered either lucky or careful, depending on your point of view.)

Q:About how long ago was the initial purchase?
A: I bought in late 2006 and sent the unit back maybe 2 weeks later.

OK - back in 2006 there were some TTL Maxyz modules floating around, and yeah, those may not have been protected against having greater than 5 volts on the modulation lead. That problem was fixed with the later analog driver. (I've connected up to 9 volts on the modulation lead on mine with no adverse effects.)

Also, it seems that the *latest* versions (shipped in early 2008) have reverted to a more basic driver that may also lack the over-voltage protection on the modulation line even though the driver is still analog-capable. I haven't tested any of these newer units myself, but posts from others (including a picture of the innards of a dead unit showing the driver components) suggest that there's no protection on the modulation input anymore.

I do not belive my failure mode could have anything to do with back- reflection (AKA Backscatter). The unit was operated on my test bench and the beam was terminated on a black aluminum surface. After the failure the unit still outputs 1mw with the beam looking exactly like it did at full power (Crosshair pattern common to this unit). It really does seem like TTL control failure or PSU failure

Usually over-current will cause the same symptoms as back-reflection, which are identical to the ones you describe above, so that really doesn't tell us anything. However, given your description of your test setup, it does seem to rule out back-reflection.

Note: Backscatter is not really the same thing as back-reflection. Back-reflection kills the diode by dramatically increasing the optical power at the face of the diode. Since the diode is running so close to maximum, by sending the beam back along the same path, the optical power density at the face exceeds the damage threshold and the face is ruined nearly instantaneously. The important difference is that a significant percentage of the output beam is reflected *directly* back to the diode, as opposed to simply being scattered off a rough surface back in the general direction of the diode.

A: OK I was a bit confused by your first email thinking that MAXyz was in good standing on this site.

His status has been changing lately. As of this time last year, his standing was among the best. So good, in fact, that Bridge (LaserWave representative) agreed to send him a 100 mw DPSS blue laser so he could do a long-term test-to-failure on it. (Note that we haven't had an update on that test in many months!) So at one point his reputation was golden, which is why so many members here are using his modules.

Lately, his reputation is not so good. As more and more stories emerge from members that have paid for their lasers and not received them, or have sent their lasers back for repair and not received them, people's opinions have changed. At this point, due to the utter lack of communication from Chuck, I believe most people have completely written him off.

I also last heard from chuck via ebay in May 08 via ebay. He seemed very willing to help and asked me what my serial number was. It was after responding to him with the details that I never heard back.

I think most people lost touch with him around that same time period. Since then, I do not believe anyone here has heard from him.

So sad because I need that darn 660 to complete my RGB projector

There are alternatives coming. Mecheng 3 is working on a 660 nm replacement laser that should be available soon. It will have similar beam specs and power ratings, but be less expensive and have a better warranty. Details to follow soon.

Longer term, several people are working on either 650nm or 635 nm solutions that should have similar beam specs. Stay tuned to PhotonLexicon for details...

Adam

[mliptack]

Possibly. Or maybe you've never reflected the beam back into the diode. (which might be considered either lucky or careful, depending on your point of view.)

I think no matter how careful you are there is still a bit of luck involved in not ruining diodes from back reflection... lol

His status has been changing lately. As of this time last year, his standing was among the best. So good, in fact, that Bridge (LaserWave representative) agreed to send him a 100 mw DPSS blue laser so he could do a long-term test-to-failure on it. (Note that we haven't had an update on that test in many months!) So at one point his reputation was golden, which is why so many members here are using his modules.

Lately, his reputation is not so good. As more and more stories emerge from members that have paid for their lasers and not received them, or have sent their lasers back for repair and not received them, people's opinions have changed. At this point, due to the utter lack of communication from Chuck, I believe most people have completely written him off.

While I do find it sad to see him fall off the way he did. I too fell off the face of the earth in a similar manner and from my experience it can be a bit overwhelming to catch back up. Regardless, I do not look down at Chuck, he really helped our side of the industry and brought a lot to the plate. Showing what could be done. The downside of running a business where as many as only two people know the 'secrets' it can be really hard when they disappear to fix modules still within warranty. And it is unfortunate. Chuck if you are still out there and possibly reading this just let it be known that we still hope the best for you and hope your back is healing. Hopefully we will hear from you again.

Anyway, like I said, I disappeared, and it is strange, the photonlexicon notification emails slowly started to die off and while I didnt forget about PL, it was put on the back burner for me. The hobby I still enjoyed a bit while I was gone... unfortunately I sold some of my gear, but hopefully soon I will be back up and fully running. Hopefully my RGB will be complete and in a nice housing by this time next year.

Hopefully I didn't go too off topic here.

-Max