405nm AR glass lenses - fit AixiZ FEELER

[Krutz]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

interesting, Zom-B!

i played around too, and will use dvd objective lenses for my projects. the beam should be so tight that focussing wont be needed at all! divergence will go up, lets see how it looks in real-life!

manuel

 

[Jimmymcjimthejim]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Results are looking good!
I have a question though:
If the lens is going to be just like the Meredith one, wouldn't that mean that the diameter of the beam is going to be wide?
Oh, and what is NA?

 

[chopper]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Results are looking good!
I have a question though:
If the lens is going to be just like the Meredith one, wouldn't that mean that the diameter of the beam is going to be wide?
Oh, and what is NA?

I think it is the numerical aperture as that's what NA stands for with fiber optics.  If that is the case it is the sine (trig function) of the largest acceptance angle of incident light, measured from the normal (perpendicular) to the lens.

This would mean a higher NA corresponds to a larger amount of light collected.

 

[artix]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Igor, I might want to change from broadband to blu-ray! ;D

 

[Jimmymcjimthejim]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

[quote author=Jimmymcjimthejim link=1212842385/480#497 date=1225312554]Results are looking good!
I have a question though:
If the lens is going to be just like the Meredith one, wouldn't that mean that the diameter of the beam is going to be wide?
Oh, and what is NA?

I think it is the numerical aperture as that's what NA stands for with fiber optics.  If that is the case it is the sine (trig function) of the largest acceptance angle of incident light, measured from the normal (perpendicular) to the lens.

This would mean a higher NA corresponds to a larger amount of light collected.[/quote]
Ok, thanks.
Oh, and..
FIVEEEE HUNDREDDDD (posts in this thread.. also my post count but I got 500 a while ago)

 

[IgorT]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

If the lens is going to be just like the Meredith one, wouldn't that mean that the diameter of the beam is going to be wide?
Oh, and what is NA?

Umm, what do you mean wide? The AixiZ acrylic lens has a FL of 7.3mm. The Meredith has a FL of 4.6mm. That's a BIG difference! I was actually hoping for something like 5.7mm. 5.7mm and 7mm dia allows for a high enough NA, but isn't too short a FL, so focusing would work better.


I tested a Meredith with a red, and it makes a beautiful round beam, not too thin, but noticably thinner than AixiZ. If you go even thinner than that, focusing becomes very hard. At a distance, the focus is just too spread out. Not to mention, that divergence increases dramatically.

With a PHR and a Meredith, the beam is also thinner, however a PHR has a thin but wide output. The Meredith makes a thinner beam, but it also collects more light - more of the fast axis. The result is a beam, that looks even flatter, than usual. But that's because of the diode output, and becausee of the fact, that the Meredith collects all of it. Every high NA lens will do this.

The only way to create a round beam from a flat output diode is to clip it with a low NA lens. The AixiZ has such a low NA, that it makes a PHR output oval, even tho it's not. The only way to create a super thin round beam is to use a short FL lens with a low NA. Low NA means losses. We want max power.


Well, there is another way to make a beam round - corrective optics, like an astigmatic lens, or a special lens, that first collimates the fast axis to give it the same divergence as the slow axis, and then collimates both into a thin beam. But those lenses can not work in a rotary system. If you turn such a lens just a little, it will distort the beam instead of making it rounder.


In any case, the Meredith makes a red beam noticably thinner and it looks very round. But a PHR beam looks almost as wide as AixiZ, only flatter. With a better blu diode, the beam will be more like a red beam, altho it will still be slightly fatter. It would take two different lenses, to give both a red and a blu the same beam diameter.


The third lens has an eveen shorter FL, so it will compress the beam further, but it will make focusing harder and divergence higher. With a PHR it will still be flat tho. That's because the PHR is a weird low power diode, almost multimode.


In any case, i only really know what lens #2 will look like. Not the other two. I will need to test them. That's why i paid for them - to get to see the final results!  So let's do the testing first, and then we can decide what we want.

 

[IgorT]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Also, i don't know if you all realize how much more dangerous a needle thin beam is..

I gave my 6x a lens, that made the beam almost as thin as a green pen. No idea about the precise FL. It did 240mW (from 213mW with AixiZ lens), even tho the NA must have been low, as the beam was almost round, and it lit matches, and even a cigarette with a parallel beam!

If you get THAT into your eye, it's impossible not to get permanent damage, because the energy density is so much higher.

 

[Kenom]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

That in and off itself is one of the attractive things about a thin beam. It means not having to adjust focal length to get burning power. Truly it is more hazardous and if your gonna be playing with high powered lasers without some kind of eye protection then you've really got nobody but yourself to blame.

 

[Jimmymcjimthejim]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

[quote author=Jimmymcjimthejim link=1212842385/480#497 date=1225312554]
If the lens is going to be just like the Meredith one, wouldn't that mean that the diameter of the beam is going to be wide?
Oh, and what is NA?

Umm, what do you mean wide? The AixiZ acrylic lens has a FL of 7.3mm. The Meredith has a FL of 4.6mm. That's a BIG difference! I was actually hoping for something like 5.7mm. 5.7mm and 7mm dia allows for a high enough NA, but isn't too short a FL, so focusing would work better.


I tested a Meredith with a red, and it makes a beautiful round beam, not too thin, but noticably thinner than AixiZ. If you go even thinner than that, focusing becomes very hard. At a distance, the focus is just too spread out. Not to mention, that divergence increases dramatically.

With a PHR and a Meredith, the beam is also thinner, however a PHR has a thin but wide output. The Meredith makes a thinner beam, but it also collects more light - more of the fast axis. The result is a beam, that looks even flatter, than usual. But that's because of the diode output, and becausee of the fact, that the Meredith collects all of it. Every high NA lens will do this.

The only way to create a round beam from a flat output diode is to clip it with a low NA lens. The AixiZ has such a low NA, that it makes a PHR output oval, even tho it's not. The only way to create a super thin round beam is to use a short FL lens with a low NA. Low NA means losses. We want max power.


Well, there is another way to make a beam round - corrective optics, like an astigmatic lens, or a special lens, that first collimates the fast axis to give it the same divergence as the slow axis, and then collimates both into a thin beam. But those lenses can not work in a rotary system. If you turn such a lens just a little, it will distort the beam instead of making it rounder.


In any case, the Meredith makes a red beam noticably thinner and it looks very round. But a PHR beam looks almost as wide as AixiZ, only flatter. With a better blu diode, the beam will be more like a red beam, altho it will still be slightly fatter. It would take two different lenses, to give both a red and a blu the same beam diameter.


The third lens has an eveen shorter FL, so it will compress the beam further, but it will make focusing harder and divergence higher. With a PHR it will still be flat tho. That's because the PHR is a weird low power diode, almost multimode.


In any case, i only really know what lens #2 will look like. Not the other two. I will need to test them. That's why i paid for them - to get to see the final results!  So let's do the testing first, and then we can decide what we want.[/quote]
Wow, Thanks for the info!!!
I never had any experience with the Meredith glass lens, so I don't know much about it.

 

[robjdixon]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Any new information on these?

 

[hydrogenman15]

I'm in for one.

--hydro15

 

[hydrogenman15]

I'm in for one.

EDIT:
*I'm in for one 405nm AR coated glass lens*

--hydro15

 

[Lasercrazy]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Any chance we'll have the lens in our hands by the end of the year?

 

[lazerjules]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Hi,

I am definately up for 2 of each to start with!
more if they are good.

 

[IgorT]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

The custom lens is at the customs...

I am preparing the papers now, to get them released, and i will have the final three models in my hands tomorrow!

 

[drlava]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Also, i don't know if you all realize how much more dangerous a needle thin beam is..

I gave my 6x a lens, that made the beam almost as thin as a green pen. No idea about the precise FL. It did 240mW (from 213mW with AixiZ lens), even tho the NA must have been low, as the beam was almost round, and it lit matches, and even a cigarette with a parallel beam!

If you get THAT into your eye, it's impossible not to get permanent damage, because the energy density is so much higher.

Your eye does the focusing onto the retina itself, so the energy density is even higher than you think. The only way a thicker beam will be safer for the eye is if it is wider than the pupil. So beams 10mm or less are all similarly dangerous, only when the beams get much larger than 10mm dia does the danger factor begin to decrease.