405g2 problem

[edison]

Hello guys

I recently purchesed 50 405g2 lenses from laser66 to collimate blue diodes. I ordered 50 at once because the first time i ordered them i was very happy with the quality.

I tried about 12 lenses from the batch and they have all the same problems. The area arround the stripe is not clean like the ones before.

I,m pretty sure laser66 switched to a new supplier but i wasn,t notified before ordering.

I wondered if anyone has the same problems with the new lenses. Does anyone has the same experience?


Here are some pictures from the lens in focus on 10 meter:

[Solarfire]

Hello guys

I recently purchesed 50 405g2 lenses from laser66 to collimate blue diodes. I ordered 50 at once because the first time i ordered them i was very happy with the quality.

I tried about 12 lenses from the batch and they have all the same problems. The area arround the stripe is not clean like the ones before.

I,m pretty sure laser66 switched to a new supplier but i wasn,t notified before ordering.

I wondered if anyone has the same problems with the new lenses. Does anyone has the same experience?


Here are some pictures from the lens in focus on 10 meter:

Have you tried a different diode?

[edison]

yes i have no improvement what so ever. I even have cleaned them with first contact to make sure that they are clean as they can be. Also no improvement.

[Solarfire]

Hmm.. dose the splash around the beam appear to rotate when adjusting focus.
Were the lens pre mounted?
Do you have the posibility to try a different lens retainer/barrel?
Are the lens and exit window of the diode(s) absolutly free from contamination?

[edison]

I use the retainer that is specially made by dave. Never had problems with those. they are spot on. I tried everything different barrel , different diodes etc. Yes the diodes are perfectly clean. I tried other lenses like o-like,s that are also brand new. Those give a perfectly clean beam.

[logsquared]

Out of 10 I have used 1 did exactly what you describe and the power was down maybe 40% or so (can't remember exactly). Also did everything you described... changed diodes, cleaned,etc.

[logsquared]

Wanted to add.. I think the original 405g was a Rochester A671 lens. http://ifolomedia.com/~rpoptics/uplo...alog_109A4.pdf

[andy_con]

edison the latest one i ordered was the same as yours

[edison]

Thanks losquared. Good to see i,m not the only one. Yes the original 405g was the rochester and i ordered those the first time. I made 16 modules with those and i was happy with the quality and clean collimation from them but with the latest the results are far worse.

Thanks Andy, it seems that maybe a bad batch slipped true or that Will decided try another supplier. He said the ones that i recieved where from the same supplier so it must be a bad batch?

But i have 37 lenses that i can,t use and 5 people that waiting on there 2 watt modules. Also the UKlem is coming up and dimitri was planning to show his 2 watt module.

Vjernst and richard are waiting in there modules. I think everyone here that build modules are in need of a supplier with a steady quality even if they are a few bucks more .

If anyone has similar results please come forward so this can be sorted.

[Solarfire]

Out of 10 I have used 1 did exactly what you describe and the power was down maybe 40% or so (can't remember exactly). Also did everything you described... changed diodes, cleaned,etc.

Do I understand correctly, you have a 40% power loss with one of your 405-G-2 lens?

@ Edison
Have you done any power measurements to determine loss? I haven't bought any recently but all the ones I’ve got are absolutely top and clear as a bell. Have you gotten in touch with Will about this?
The O-Likes will tend to be cleaner due too the much longer FL. Try an optima if posible.

[logsquared]

Do I understand correctly, you have a 40% power loss with one of your 405-G-2 lens?

@ Edison
Have you done any power measurements to determine loss? I haven't bought any recently but all the ones I’ve got are absolutely top and clear as a bell. Have you gotten in touch with Will about this?
The O-Likes will tend to be cleaner due too the much longer FL. Try an optima if posible.

Yeah, it was around 40% and the spot could not be focused cleanly.

The 4mm optimas seem to work great on the 445's. (I just dropped yours of at the post BTW)

@Solarfire
Have you A/b tested the optimas against the 405g? I don't have 405g to test with or a 445 with know measured power/ current curve.

[edison]

Yes the optima has the same FL so the results are quite good. They might have a little bit more losses. I have aboutt 20 of these so i will finish 1 blue with them. But the first 405g2 that i had where very good. Most people where very satisfied and everyone noticed the cleanless of that lens. Not sure what happend now.

[chad]

Send them all back. Let will figure out what is going wrong. IF the lenses are bad there is no reason that you should have to keep them.

chad

[edison]

I contacted will already about the problem and waiting for his call what to do. hopefully its getting sorted some how

[olive13]

Maybe a Scratch/Dig or bad coating pb
check with microscope...

[edison]

Well could be. I,m pretty sure its the coating because the stripe when setting the lens in focus is fine. It causes also backreflection so that will damage the diode for sure. I fried 4 diodes until now. so another 200 euro down the drain.

Solarfire would you do the honour if i send a few to you to find out what the cause is. You are pretty experianced in my opinion when it comes to lens testing. I have 37 of them and i would like to have a replacement. I haven,t recieved another email from will by the way, i,m still waiting.

[logsquared]

I just wanted to clarify my post from earlier. I have only owned a total of 10 405-g's of which 1 was bad. The one in question I bought over 1.5 years ago and it didn't come from laser66. So, I'm guessing my dud is unrelated to edison's duds.

[kiyoukan]

interesting supplier of optics.
Thanks for the link hate to hear bout your problem tho.
The coating process from where i got mine done is very automated, it might be more likely it was contaminated glass.
But what ever it is it will be interesting to hear what caused it.

[edison]

I,m thinking of sending solarfire a few since the lack of responce of laser66. The thing is that with a problem of a part it not only has effect on me but also on the customer. Most customers need to do shows to buy my modules so if they have to wait on my module they can,t do the show and so they can,t invest in more projectors and such. I learned that the key about developing a good product is not the design its self but to get suppliers arround you that can help you out within a day or 2. True the bad lenses i fried 4 diodes and had to take a dual blue apart and build it al the way up. That means that the PBS, waveplate cannot be used again so this dual cost me already 4x50 euro and 50 euro for waveplate and PBS.

Everyone that is building something make sure that you have good quality stuff to work with. I noticed a few weeks earlier but i didn,t think that it was a problem. The stripes are not nice but i didn,t expect that it would cause back reflection that kill the diodes.

I,m sure that Will can solve the problem and i hope that he does.