635nm C-Mount Diode

[anselm]

I'v looked into making my own driver and understand that it must be reverse of the usual build

What do you mean by that?:thinking:
Do you know the diodes forward voltage, lasing threshold current, operating current?
What's stopping you from making a simple linear driver, you know, the old DDL LM317...

 

[532 with Envy]

By reverse I mean that most of the DIY drivers that I see are Positive regulated, where as, from what I understand I need a negative regulated.....

The diodes forward voltage I think is 1.8-1.9V
Not sure what the lasing threshold on this diode is, but the operating current I'm looking for is around 800mA.
That should give me around 280mW.

 

[anselm]

from what I understand I need a negative regulated.....

As far as I understand it, you only need to worry about that if the diode is case
positive and you have it electrically connected to Vcc.
Aren't you building a labby?
It shouldn't be so hard to keep the diode's case isolated, so you wouldn't have to worry about that.

Or how do C-mount's work? Do they even have dedicated anode and cathode pins, or do you
HAVE to use the case as an electrical connection?

You know like green modules are case positive too, right, and the driver is a negative
regulator? Well I have hooked up a LM317-like (LM1117 actually) driver to the
pump diodes + and - pins and it works just fine.

 

[rhd]

Anselm is correct -

The C-Mount is case positive, which means that a PORTABLE build will require a driver different from the typical DDL setup we use frequently here. So 532WithEnvy is correct as well. If he was making a portable, he would (absent a bunch of tough electrical isolation) need to create a "negative-regulating" version of the DDL setup.

However, if you're making a labby, that complexity all disappears. You can use pretty much any driver you want, as long as the case that your diode is connected to doesn't need to carry the charge. Truthfully, I can't see any reason why it would, so you should be safe!

 

[532 with Envy]

It is a lab build and isolating the heat-sink that the diode on will be no trouble.
I'm actually going to mount the diode test-jig onto a copper sink, and there is a spot to attach the wire for both positive and negative leads.
Most of all this is just to make sure I can use a flexdrive or something similar before I go plugging in the diode and firing it up. This is a great weight off my mind....all the reading trying to figure out a negative-regulating driver I forgot that I don't have to worry about the diode isolation from a host.


Thank you both for your input on the driver......almost there on my design......
I think it will look very cool and hopefully work great!

Now onto lens!......:thinking:

 

[532 with Envy]

So I have done some more optics research and still am not sure if I have my head around it....Perhaps some input.

For your HUGE ENJOYMENT....I did a paint drawing.....Please mind you I am NO ARTIST!
Notice the type of lens that I am thinking of and also the Focal Length and if I have my thinking correct there as well.

Thanks for everyones help

[/IMG]

EDIT: I should mention that the diode DOES have a FAC lens on it which should help quite a bit from what I understand

 

[anselm]

I don't know jack optics, but if I were you, I wouldn't risk blowing the precious microflex
from a potentially unregulated, noisy, spiky chinese wall-wart....:undecided:

 

[532 with Envy]

I don't know jack optics, but if I were you, I wouldn't risk blowing the precious microflex
from a potentially unregulated, noisy, spiky chinese wall-wart....:undecided:

Are there regulated wall-warts? The radio shack just up the street from me has a huge amount of different wall-warts and I was hoping for an easy hook-up from driver to wall.

 

[532 with Envy]

I did find a nice Regulated enercell selectable 3/4.5/6/7.5/9/12V 1A Ac adapter. I think that this will work for what I need. (unless there is someone out there that has a better idea to allow the unit to be powered by just a wall plug.)


Okay, I still need to ask of those in the know about the optics.
The farther I go the more I learn but am still confused.
I'v seen that I might be able to use a Plano-convex, or a Double-convex, or perhaps a combination of a positive and negative cylinder lens..........

PLEASE HELP SOMEONE....I really don't wan't to go out buying all kinds of coated optics just to see if they may or may not correct/collimate the beam. I understand it may even only be one piece of optics to get a nice collimated beam because of the FAC already installed(which should make the output a square shape?)

Please understand that I have been doing quite a bit of reading and think that i'm getting pretty close to the answer here but just need a bit of pro input to point me the right way. I should also mention, if it matters, that i'm planing on using lens that are 1-1.5 inch in diameter because it fits my build and also will make any alignment that much easier on me.

I do have some pretty nice bits of optics from a a-140 projector tear down, but from what I read they are all for 445nm and i'd get a lot of loss using them.(and i'm not sure which to use)

It's almost there and if all works out I think everyone will enjoy it

 

[anselm]

Well just for experiments to see what kind of lens works, you can use optics wih the
"wrong" coating, no? You wouldn't get maximum power, but once you find a combination
of lenses that work, then you could worry about getting some of those with the correct coating....

I'm guessing (not knowing actually) that if you wire a capacitor across the power
source wires, that should attenuate noise from the adaptor...

 

[532 with Envy]

Well just for experiments to see what kind of lens works, you can use optics wih the
"wrong" coating, no? You wouldn't get maximum power, but once you find a combination
of lenses that work, then you could worry about getting some of those with the correct coating....

I'm guessing (not knowing actually) that if you wire a capacitor across the power
source wires, that should attenuate noise from the adaptor...

I have thought of using these optics for experimenting which will be best, but ideally I would like to have my whole assembly ready to go as close to possible before I install the diode.(avoiding 'open air' experimenting)
If I can't find the correct answers i'm looking for I may have to build some sort of test rig that encloses the diode so I can try all the different lens ideas and see what works.(really want to avoid this though)

With the wall-wart....that capacitor is a good idea and couldn't hurt anyways I would think, and extra line of defense.

Thanks Anselm and others so far on your input with this build. :thanks:

 

[Kevlar]

Are you still in need of optics for this build? I would love to see this come together. :tinfoil:

Unfortunately I can't offer any advise on which optics to use but I do have some you could try. :san:

I recently pulled apart an old laser printer and "acquired" what look to be 3 quality lenses.

1 positive meniscus 31mm diameter
1 bi concave 27.17mm diameter
1 bi convex 27mm diameter (AR coated)

The bio convex has an AR coating that very strongly reflects a deep-orange. I don't know what wavelengths it is coated for but I'm pretty sure the laser printer I got them from had an IR diode in it. All 3 were mounted next to each other. I have some pretty good pics I can post if you'd like.

Anyway, I figured I'm not doing anything with them and thought if you wanted to try them out I could send them to you. If it works out great, if not just send em back. :beer:

 

[532 with Envy]

Are you still in need of optics for this build? I would love to see this come together. :tinfoil:

Unfortunately I can't offer any advise on which optics to use but I do have some you could try. :san:

I recently pulled apart an old laser printer and "acquired" what look to be 3 quality lenses.

1 positive meniscus 31mm diameter
1 bio concave 27.17mm diameter
1 bio convex 27mm diameter (AR coated)

The bio convex has an AR coating that very strongly reflects a deep-orange. I don't know what wavelengths it is coated for but I'm pretty sure the laser printer I got them from had an IR diode in it. All 3 were mounted next to each other. I have some pretty good pics I can post if you'd like.

Anyway, I figured I'm not doing anything with them and thought if you wanted to try them out I could send them to you. If it works out great, if not just send em back. :beer:

Thanks again for the offer! I ordered a few different lens from surplus shed to experiment with.

I have developed a problem though. I was noticing a drop in output when I left it on for just a small amount of time. I think that my design does not cool well enough......so I have been in re-design that will incorporate a TEC cooler for the diode mount. The whole unit is changing around but I think I stopped messing around before I destroyed the diode(I Hope)

I'll keep everyone up to date when I get more put together, I know have to learn what I can about TEC's and how to power and control them.(more reading):beer::beer:

 

[Cyparagon]

It's bi-concave. Bi for 2 meaning both sides are concave.

 

[Kevlar]

It's bi-concave. Bi for 2 meaning both sides are concave.

Thanks for pointing out my typos. :beer: Actually, I have biology on the brain. I was doing CEs to re-up my Pharmacy license.

 

[532 with Envy]

All my reading on optics has been very interesting so far, even though I'm not totally sure what to use yet, I think I have most of the lens that might work here or on the way in the mail.
As soon as I get my new design worked out and how to drive my TEC and FAN i'll get some pictures up.
Thanks everyone for your input, I hope in the future these thread will help others to work with C-mount diodes.