405nm AR glass lenses - fit AixiZ FEELER

[TheGr8Revealing]

I just received a response from Meredith Instruments about their glass lens.
They say, that the Meredith glass lens has an MgF2 AR coating optimized for 655nm.

The 405nm custom lens will also have an MgF2 AR coating, but optimized for 405nm. It also consists of a glass material with which this type of coating works particularly well (refractive index of 1.9.. regular glass =1.5).

And since it is very similar to Meredith in all aspects, only a bit larger (with a higher NA as well), there is no reason it should not work just as well.


I hope i receive another comparative measurement (AixiZ acrylic & Meredith) soon, and we should know more then.


I'd say it's looking pretty good for now.

Is Meredith also going to be offering a custom AR coated glass lens for their housings as well then?

 

[OrBy]

IgorT put me down for two please.

*edit - make that one 405 and one multi.

**edit again - Make that two 405's and no (0) multi's.

 

[IgorT]

Is Meredith also going to be offering a custom AR coated glass lens for their housings as well then?

What do you mean? I just wanted to say, that Meredith Instruments confirmed, their lens is AR coated for 655nm. In the meanwhile, i also received the datasheet, and it says the Meredith glass lens is has a coating for 655-810nm, with a transmission of 95% at these wavelengths..

At a different wavelength, like the 405nm, the same coatings would do the opposite of what they are supposed to - they give the light additional surfaces to reflect off. That's why the power decreases a bit with lenses coated for the wrong wavelength. A coating is supposed to decrease reflective loses, but the wrong coating can double them.


What i meant was, that the Meredith really is coated for reds, which means, a lens with the correct coating, should be a bit better.
And if the Meredith increases power by 30%, compared to AixiZ acrylics, then it could be interesting... Jayrob measured a 30% increase at different power levels, which usually means, that the percentage is correct.


I should also be receiving a Meredith module soon (thanks again, Daguin!), so i can make some comparative measurements myself. I want to verify the power difference on my meter.. When i get it, i will post the results. It should give us an idea of what to expect.

 

[Kenom]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

I would like to get one of the 405nm lenses as well pending the results of the testing.

 

[jayrob]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

I did that as well, but i get 120mW when there is 91mW after an acrylic lens.
And this would fit with Jayrob's results from the Meredith lens, that puts out 117mW, when there is 90mW after an acrylic. He measured a 30% increase from acrylics at various powers, when he put a Meredith in.

So there should be room for 30% of improvement. But only testing will tell for sure.. As i said, this thing ain't starting until the testing results are in, verified by several people. Then everyone can decide if they want the lens or not. This thread is just to figure out how many people would be interested, if it works, and what the price would be.

I'm not promising anything, other than that i will buy and test the samples, and if they test good, make sure others can get them too.


BTW, did you have the diode in a module, when you did that test? What current was it set to?

Just to clarify here....I found a 30% increase from Meredith acrylic vs Meredith glass. I have since found that for the 405nm wavelength, that the AixiZ acrylic lenses give more power than the Meredith acrylics.

Earlier, I thought that the Meredith acrylic lenses were the same as the AixiZ acrylics, because they are pretty even using the red diodes. But not the blu-rays!
Jay

P.S. I also adjusted my multiplier for the LPM-1. Based on 6 X comparisons with GooeyGus. Plus Lava's 405nm graph. Check here:
http://www.laserpointerforums.com/forums/YaBB.pl?num=1213683861

 

[Glaserfan]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

I'm in for at least 1 depending on results/price

 

[airy52]

interested, 1x 405nm coated.

 

[iewed]

When can we expect to see the results?

 

[nvmextc]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Put me down for 2 UV coated and 1 multicoated in Aixiz nuts plz

 

[IgorT]

I was very busy during the last week, and i still am.. Will update the list, when i have some more time..


We can expect the results, when i get the first batch of the lenses. I am waiting for a reply from the manufacturer just now. I will have to send them the money some day this week i guess. Then the lenses have to ship to me.



Otherwise, as Jayrob said, there was a mistake in his lens comparisons.. I must have bugged him 10 times a day for two weeks (sorry Jay), to figure out if there could be a mistake, but the one thing i did not exclude was the AixiZ acrylic lens actually being a Meredith acrylic lens.. And the Meredith acrylic is AR coated for reds, which is why the difference to the Meredith glass was larger, than it is to an AixiZ acrylic.


Since the Meredith is the closest thing to the custom lens there is, only coated for reds, i was using info about it to get a certain baseline for what to expect.. If the Meredith would do 30%, like originally believed, this would mean we can expect over 30%.. But the Meredith only increases the power by 13%..

What this means is, that once again we do not know what the diode is actually putting out. But it does not affect the custom lens itself. The transmittance of the custom lens is known, and it will bring out all there is (as much as possible for a lens). The final power depends on one thing alone - how much light there is behind the lenses.


When i gave the production of the lenses a go, i did not have any expectations in percentage. I just wanted to get the best lens for blu rays, as i knew all other lenses have problems with 405nm. So the actual number does not really matter to me. I would prefer more of course, but i just want the best there is.

But the percentage may matter for others. Which is why this thread is meant for testing and figuring out the price.



But while i do not have a baseline anymore, i have thought about it a lot, as well as talked to some people who know a hell of a lot more about it than me, and we do still have certain expectations...

As i said, the Meredith glass only increases the power by 13% compared to clear acrylics. But with reds, the Meredith glass increases the power by 20% compared to AR coated acrylics. And a few percent more compared to clear acrylics.
The reason it is not as good with blu rays, as it is with reds, is because of the coating. An AR coating is supposed to reduce reflective losses. But the wrong AR coating gives light two more surfaces to reflect off, in addition to the two faces of the lens. This is why it reduces the power compared to a clear lens and even more compared to a lens with the correct coating..
If the Meredith glass was AR coated for 405nm, it would be at least as good with blu(e) rays, as it is with reds.. And since red light does not have a problem with plastics, while near UV does have a big problem with plastic materials, this increase could be higher, than it is with reds.


If you look at an AR coating, you can only see it, if you reflect light off of it. And a 650nm AR coating looks blueish. This is because it reflects blue light - it passes red, better than a clear lens would. A 405nm AR coating looks brownish red. It reflects red, but passes blue, better than a clear lens would.

So while we won't know the actual power until i measure it with the custom lenses, i do know one thing. It will be the best lens available for blu(e) rays.


I will post updates and testing results as soon as i have them...

Thanks to Daguin, i also have a Meredith glass lens now, so i will be able to do all the measurements myself, under the same conditions on the same meter. I am even receiving two more meters (for testing), so i can confirm the results...

 

[IgorT]

Lens update!


I got the reply i was waiting for.. The manufacturer says the lenses will be finished by the end of the week. They will ship them next Monday or Tuesday..

I am supposed to decide on the shipping method. UPS would come on the next day but cost around 80 Euro. That would increase the price for almost 3 Euro per lens.. Regular post would take 5 days and only cost 10 - 15 Euro. So i guess i'm doing that. Which means i'll have the lenses in my hands in two weeks, if all goes according to plan.


Can't wait!

 

[GooeyGus]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

will this just be the first 'test' batch or will it be the full thing? I cant wait to do some testing on the 6x

 

[daguin]

will this just be the first 'test' batch or will it be the full thing? I cant wait to do some testing on the 6x

This is his "test batch."

I think he said that he will only entertain a GB if they prove to be better than the lenses available.

Peace,
dave

 

[IgorT]

This is about the first "test" batch of lenses. I can't risk other people's money before we know if it's worth it to those same people. After the lenses are tested, and we know what they can do, people on the list can decide if they want them. Then we could do a GB.

This thread is mostly just to figure out how the lenses perform, and what the price would be, because it depends on the number ordered.


If they test well, the "full thing" can be made in another two weeks i think.. But i'll ask to make sure.

 

[Kage]

I would go for a couple of these at least, if/when a group buy starts!

 

[docjohn]

I will take 2 405nm and 2 multicoat if they test out better