405nm AR glass lenses - fit AixiZ  FEELER

Re: 405nm AR glass lenses - fit AixiZ  FEELER

I will make pictures and everything as soon as i have some time.. I have a lot of work at the moment..


Artix: I understand what you mean. Like i said, i will try to order some #7's with the GB, hopefully the manufacturer will give me a nice price on them. Cos otherwise they cost $48.50..

The v7 (aka Lens #1) can also easily be mounted in a regular AixiZ lens nut, while still allowing a focusing ring to be attached.. So a small number of those i could mount myself....


Otherwise, there is no issue with v8 (aka Lens #2). The issue is with diodes - they don't have nice outputs....

If you put lens #2 into a red laser, you get a very thin almost round looking beam (in smoke it becomes obvious it is not round tho). It is a beautiful beam. You can ask anyone, who uses a Meredith module - the specs of both are the same....

The "problem" is with blu ray diodes we have available at the moment. They do not produce an even beam profile.
They have a strange output shape, and the lens brings this out.

In presentation pointers or weapon sights spot shape is prefered to power. They use a 5mW diode, which produces a thin, flat, almost rectangular beam, but they use a lens with a VERY low NA, that clips everything but the middle of this flat stripe, making the spot look round, at great loss of power, which does not matter there.

But Lens #1 actually increases the power compared to acrylics by some 17% or so... And while the spot isn't round, the ugly edges of the fast axis are cut and rounded off. That creates a nicer spot, the beam is thinner than with acrylics, but still has some volume and focusing is still easy..


Lens #2 is the maximum power lens. But since blu ray diodes have a nasty output with some leaks at the side, this creates a spot with bent edges and a leak projected next to it.. These leaks are projected out with any lens. But with longer FLs they are so close to the spot, that the glare hides them. With short FL lenses they get projected slightly away from the spot, and make some kind of weak pattern off to one side, different with each diode.

But there is no other way to get max power out......


I would love it, if we could afford both lenses and allow everyone to select. But we need as many orders as possible, just to get the price down...


Anway, i have these filters, that show the spot shape very nicelly. I'll take some pictures.

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Krutz said:

another thought: IgorT, you invested *so* much time and money into this, and mentioned your 'other' life is demanding as well currently. if you ask, i bet some other people will gladly get the nuts (and pinhole) designed and ordered for you, for us!

just some thoughts..

manuel, excited all the time in this thread!

Click to expand...

I do enjoy the benefits of A LOT of help from MANY people here! People without whom i would have gone crazy in this time.

Besides, i just mentioned how i imagine the lens nut, and Rkcstr instantly drew one! DarkHorse said he can make a CAD model from a dimensioned sketch, so together we will get this thing sorted out!


And what amazing times these are! Imagine what one of these lenses will do on a 12x Blu Ray writer diode! 300mW, here i come! ;D



Otherwise, you are absolutelly correct! The NA can be lowered by an apperture! That is what AixiZ lenses do. Their NA is low as is (0.3), but those 5mW diodes put out a narrow stripe even through such a low NA..

But the plate in the back with the "pin hole" loweres the NA additionally, rounding the narrow stripe down to a dot.


So this is not a bad idea at all! We could have a back cover, that would clip just enough of the fast axis edges to make it less ugly with PHRs, and remove some of those nasty leaks.

I will do some experimenting to see how this would work... Lens #1 wouldn't really require this...

But Lens #2 could give either max power to those who want it, or a tiny bit less, but still a lot of power to those who would prefer a prettier spot!
It's definitelly worth looking into.


If the lens nut was properly designed, the AixiZ back plate could do the job. But metal with a clean sharp edge would do the same job better.

Room for it could be incorporated into the lens nut design, and the covers could still be done later. But the covers would need to be non reflective black! We don't want to increase reflections with lenses that reduce them to almost nothing..

Re: 405nm AR glass lenses - fit AixiZ  FEELER

pullbangdead said:

But that brings up an interesting question that no one has to respond to, just rhetorical; how do you quantify a vacancy in a glass, which by definition has no long-range order?  Ie, if there's no defined place where an atom should be, how do you define when an atom is missing from that place that isn't defined?  It has to be some kind of vacancy-like defect or something more complicated; it's certainly not simple.  My head hurts.

Click to expand...

Instead of describing the vacancy, can't we just describe the density of atoms that are their as a function of position? i.e. n(r) ... => lower n(r) corresponds to more 'vacancies'. Or maybe you could have a mean atom spacing function of position, a(r) ?

Re: 405nm AR glass lenses - fit AixiZ  FEELER

chopper said:

[quote author=pullbangdead link=1212842385/660#677 date=1226601821]But that brings up an interesting question that no one has to respond to, just rhetorical; how do you quantify a vacancy in a glass, which by definition has no long-range order?  Ie, if there's no defined place where an atom should be, how do you define when an atom is missing from that place that isn't defined?  It has to be some kind of vacancy-like defect or something more complicated; it's certainly not simple.  My head hurts.

Click to expand...

Instead of describing the vacancy, can't we just describe the density of atoms that are their as a function of position?  i.e. n(r) ...  => lower n(r)  corresponds to more 'vacancies'.  Or maybe you could have a mean atom spacing function of position, a(r) ? [/quote]


Oh my god..  ;D


Are you a physicist, Chopper?

Re: 405nm AR glass lenses - fit AixiZ  FEELER

IgorT said:

Oh my god..  ;D


Are you a physicist, Chopper?

Click to expand...

How could you tell? ;D Actually I'm finishing up my undergrad in physics and applying to grad schools now. If I stay where I am now I'll probably end up doing research with green LED's to develop high efficiency white LED lighting.

I will also have a minor in psychology so I might be able to remember how to talk to those with less nerd prowess.

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Oh, i don't know.. I'm psychic... :

Re: 405nm AR glass lenses - fit AixiZ  FEELER

IgorT said:

Oh, i don't know.. I'm psychic...  :

Click to expand...

And I'm psycho

And I have a psyche [smiley=laugh.gif]

Re: 405nm AR glass lenses - fit AixiZ  FEELER

you could all use a psychologist

Re: 405nm AR glass lenses - fit AixiZ  FEELER

And we all have something in common..  :


EDIT: Wicked, our posts should be in reverse order.. ;D

Re: 405nm AR glass lenses - fit AixiZ  FEELER

chopper said:

[quote author=IgorT link=1212842385/680#691 date=1226675267]


Oh my god..  ;D


Are you a physicist, Chopper?

Click to expand...

How could you tell?  ;D   Actually I'm finishing up my undergrad in physics and applying to grad schools now.  If I stay where I am now I'll probably end up doing research with green LED's to develop high efficiency white LED lighting.  

I will also have a minor in psychology so I might be able to remember how to talk to those with less nerd prowess.  [/quote]


Nice. Where are you applying for grad school? And where are you at now? Not a lot of places have nitrides groups for green LEDs and such, it's a pretty specialized area, but it's a great field.

Using an atomic spacing argument would be tough because of the multiple bonding species (Si, O, etc) and multiple bonding states (different bond lengths depending on what atoms are bonded together). I'm sure people have done studies on the problem as a whole, and I'm sure they included all kinds of theoretical calculations and such. And the reason normal materials always have vacancies is because the vacancies increase entropy. With a glass, everything is already random, so entropy is already very high compared to a perfect crystal. Some interesting ideas to think about, though.

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Right now I'm a senior at Rensselaer Polytechnic Institute (we call it RPI, administration wants us to call it Rensselaer).   I'm kind of banking on staying at RPI for my PhD, the program I mentioned just got big funding from the NSF and others.  Here is a link to the press release:
http://news.rpi.edu/update.do?artcenterkey=2503&setappvar=page(1)

Professor Wetzel already has complete means of production of Group III-Nitride based Semiconductors via Metalorganic Vapor Phase Epitaxy.  

More info at: http://www.rpi.edu/futurechips/index.htm

I'm still searching for the best places to apply, although time is running short.  I'm thinking: RIT, BU, Georgi Tech, maybe Cornell and Caltech if I'm feeling lucky.  University of albany probably too for a super safeguard.  I've been told that RPI rarely would reject one of their undergrads with a GPA >3.5.  I'm still waiting to get my Physics GRE scores (took it on Oct. 18), but I definitely didn't put as much into prepping for it as I should have.  I opted for less stress since RPI doesn't need the GRE for their own students.

I assume your at UCSB, how's it there?  Must be nice in sunnny CA!  The worst part of being here in Troy is the lack of clear skies and light pollution [supernerd](I'm the VP of the Rensselaer Astrophysical Society)[\supernerd].  

Re: 405nm AR glass lenses - fit AixiZ  FEELER

Sounds like a pretty good program, and a pretty good center they're starting up there. That funding level with some equipment already in place is very good. Just the one MOCVD/MOVPE system? Still, $18mil over 5 years is nothing to sneeze at, sounds like the beginnings of a very good center.

UCSB rocks, best choice I've made in years to come here. The III-nitrides program here is amazing, even being here it still amazes me. Huge number of people, huge number of cool and interesting projects covering every aspect of III-nitride devices (LEDs (UV, blue, green, yellow, white, all of them), lasers, power switching, all the way from initial growth to device packaging, and both theoretical and experimental), and working with some GREAT minds. And there's plenty of funding, so I have to worry ZERO about grant writing and the like, and stipends are more than covered. My office is 200 yards from the ocean and has a view of the mountains, and the weather is always gorgeous (at least when there aren't wildfires, then it's a bit smokey). Certainly plenty of stars for you to see, and it's only a short half hour or so drive to wilderness where there's little, if any, light for your star gazing. AMAZING place to be if you're interested in III-nitrides work.

I thought about several of those schools as well. My focus was materials, and I really wanted to work on III-nitrides, but I was open to other things as well. Georgia Tech was my psuedo-fall back (their application wasn't due until after the response dates for several of my first choices, so I was ready to apply if I missed on a couple of those), but I didn't want to live in the middle of Atlanta, at all. Not my thing. I know a girl at Cornell who loves it, but I don't like the cold (you obviously don't mind it too much with where you're at now though, so to each his own). I applied to CalTech and they brought me out there for a visit, and to be honest, I didn't like it that much. It was cool and all, certainly great minds and great history. But many of the labs were older (almost to the point of being rundown it seemed, and all of the work was very heavy theory, with very little practical application going on. About 2 professors (Atwater and Johnson) were really working on things that had immediate practical applications, but EVERYONE wants to work for Atwater, and Johnson's stuff was cool, but not that interesting to me personally. It way be an entirely different experience for physics, but that's how it was for me with materials.

UCSB ending up having a lot of brand new equipment, their program is on the rise and going places, with new innovations that are going into almost immediate production as well as deep theory discoveries, and it just fit me better. May be different for physics, but if you want to work in nitrides, there's no better place in the country. And with so much money available at UCSB in materials, it wasn't even all that hard to get in to, relatively speaking. But maybe I'm a little biased .

Re: 405nm AR glass lenses - fit AixiZ  FEELER

COULD SOMEONE PLEASE EXPLAIN TO ME WHAT IS GOING ON WITH THIS THREAD!
*Ahem*
Yeah, this GB is confusing at best.

Re: 405nm AR glass lenses - fit AixiZ  FEELER

happytomato said:

COULD SOMEONE PLEASE EXPLAIN TO ME WHAT IS GOING ON WITH THIS THREAD!
*Ahem*
Yeah, this GB is confusing at best.

Click to expand...

It hasn't advanced to the level of a GB yet so we are entertaining ourselves while IgorT continues his (much appreciated) research.

Peace,
dave

Re: 405nm AR glass lenses - fit AixiZ  FEELER

I would be interest in 1 405nm lense