Another project red?

[MechEng3]

I have had a good experience with the Aixiz lenses...but they make a fatter beam. The 2 Melles collimators I have are just unreal....@ $ 241 each. I picked them up used for a song....unknowingly they were that good. The basic idea was to keep costs down, readily available parts...most of them, and get others involved. My idea was to incorporate the Aixiz lens and the diodes in a .5" T-6 ally bar. 6 bars holding 2 diodes each. 3 pair offset diodes for H pol and 3 pair offset for V pol. The method of getting the overlap is critical to the output size. Look at the grouping pattern. Like looking onto a cleaved cable full of tightly packed strands.....I will need to draw up the block sections in detail...then it will be clear. Mr willing can your machines read from Alibre? I can output it in G code or most any format you need...if you want to make a few parts. I can usually get on a Hass machine somewhere but not anytime soon. I also though of doing the blocks in copper and ally sub- base plate...the diode blocks will be tapped for the lens and machined 5.6 mm for the diode. I will try and get something sketched up soon. The theory works....there are magic numbers on the diodes to combine most tightly. 4,5,9,12....you get the idea here.Also there is a very small amount of steering ability with the lens...secured with adhesive when aligned. The mirrors are from the sleds...best of all they are a free by-product. The H pol would be stacked and knife edged...the V pol would be the same. Rather simple if you study the original drawing and contemplate the outcome.The lens 27 may be nice...but I would like to keep the cost down on the project...this invites more thinking and being resourceful. If the block are to be machined from aluminum , I may be able to donate enough to make 4 or 5 lasers. I will have to check my materials at home. The baseplate will need to be 9mm or a bit thicker and the bottom of the laser can be .25" A single 40mm TEC can handle the cooling chores...most this size is enough Q. As for the mirror mounts...solid round stock....only pivoting about an offset drilled hole for a socket head machine screw...the tilt can be facilitated into a loose slot and adhesive to set the angle. Thought up a way to stress the shaft by slitting the side and a set screw in the top would adjust the tilt. But then it would have to be attached from the bottom making an assembled laser a pain to adjust. Still planning...thanks for the push! Is there a lens 27 GB in the near future?? What about a lasorb GB? Does anyone work with 0-80 size threading machines? If so a few of the tiny mm-1's could be made up...1/4 x 1/4.

[MisterWilling]

My machines read g code. However, if you just give me simple sketches I can draw it up and write my own code for my cnc machines. That's no problem. I also can do 0-80 tapping.
I have just built a large quantity of the brass adjustable mirror mounts and those seem to be the most stable out of all other options. They are an excellent design to make and utalize 60 tpi adjusters. Only issue I have with those is they are not my design and I would have to consult with other individuals before mass producing them.
I personally have made my own copper modules for housing diodes similar to the aixiz ones and found it not necissary if you are using TECs. It can have it's benefits without a tec but not worth the time and effort when you can the aixiz mounts for under $2.

I am interested in a lens27 group buy. Although in their price list they have 1-49 pieces of the bare lens for $27, and $34 for 1-49 pieces of the lens mounted. I have the equipment to make my own lens housing but threading m9x.5 is a pain in the ass. I used to do it for a guy and never really made much money off it for the time I spent making them.

[edison]

If you want to have good beamspecs ask Marco or Mccarot. Here,s the link with information about these lenses.

Marco has also a positive driver but you need 4 of these. KL79 has a picture of it i think.

http://www.photonlexicon.com/forums/...ght=collimator

[mccarrot]

@mecheng3

If I where you I would do it good (with good lenses) or don't do it at all.

Also when you use the lens 27, they have just metric screw in threat for lens adjustment, this is in mu opinion not fine enough for a multi diode setup because you will get alignment issues with that many diodes.

My lenses got very special fine threat for very fine adjustment of the lens and no need to secure it, a stable and thin beam is mandatory for a multi diode setup.

I think spending some more money on quality lenses will safe you allot of trouble.

[MechEng3]

OK then lets have a multiple purchase price...so maybe we can get a GB going on this lens. I have found a very attractive lens at Optics online...FL 4mm NA .6 BFL 2.4mm .25 dis DBAR 400-670nm. Ican machine my own fine thread holder...but lets see your prices so we can have a breakdown of what lenses are available....quality vs. pric. Thanks!

[logsquared]

Hey guys i just found this thread and happen to be working on a multi diode red project right now. Here are some things i have found / measured in my experiments so far.

Here are some things a found necessary for my design to be feasible:

1. Simplicity. When using large numbers of diodes like 18-36 diodes it needs to be easy to build and adjust. Also, parts should be readily available.

2. Cost. Expensive lenses sound good at first but when you do the scaling it gets real pricey. 18 lenses X $20 = $360.

3. Size. My first designs had 4 axis mounts for every knife mirror mount and a 1 axis mount for the diode mount. All with 1/4 80 adjusters. It soon became apparent this thing would be huge.

Here is where i am at after 2 months of scratching my head and a full tablet of sketches. I decided to use the aixis modules and glass lenses with the LOC diodes. I decided to use a 2 axis mount on the mirrors and a slotted mount for each diode. the mirror mounts are set and glued. This should provide the best long term stability. For mounting the mirror to the mount itself i will use a jig to place the mirror with good accuracy. This may lead to a small amount of clipping of some of the beams. This has to be accepted for simplicity reasons.

Here is some data i measured that may be useful to those designing their combiners. With a LOC in an aixis barrel with aixis glass lens @ ~ 2 inches from the lens the beam is at 82% power if put thru a .8" X .16" window, if the window is .75" X .15" the power is 78 %, and for .75" X .13" i got 75% transmission.

Using this data a 3mm X 3mm beam is attainable with a 2 rows of 4 diodes and a 2.5X telescope with 82% transmitted. ~.55 mRad

Or 3 rows of 6 (18 diodes) with a 4X telescope with 82% transmitted. ~.88mRad

Or 4 rows of 7 (28 diodes) with a 4X telescope with 75% transmitted. ~.88mRad

Just for fun. if a 5mm aperture is ok then: 6 rows of 10 (60 diode) 4X tele with 75% transmitted.

Of course any of the these can them be run thru a PBS for 2x the power.


To date i have made a few versions of the 2 axis mirror mount i think i have finally setteled on the final design. I set it up at a target ~ 100 ft away and adjusted the mount waited about 48 hrs and the mount has stayed true on target without glue. In the next few days i will have a complete 2 row of 4 combiner machined. Still waiting on the rest of my aixiz barrels to come in. oh yeah, the base size for 8 diodes is aprox 3" X 5" and for 18 diodes (no PBS used) 3.5" X 13" this doesn't include the telescope optics. I will post pics when i get it machined and running.

Question for andy_con?

I am curious to the mRad divergence of the roithner lens you use? Also, what diode is used with that lens? With the aixiz glass i can get about .2 -.225 mRad full angle. When i tried using shorter focal length lenses i did get considerable size reduction at aperture but what ever percent reduction at aperture was multiplied in divergence or far field spot size. The roithner lens must be a very special aspherical type. If the far field and near field spot size are proportionally smaller than a simple lens then they would be a god send for increasing the combined beam power density.

[logsquared]

@mecheng3

If I where you I would do it good (with good lenses) or don't do it at all.

Also when you use the lens 27, they have just metric screw in threat for lens adjustment, this is in mu opinion not fine enough for a multi diode setup because you will get alignment issues with that many diodes.

My lenses got very special fine threat for very fine adjustment of the lens and no need to secure it, a stable and thin beam is mandatory for a multi diode setup.

I think spending some more money on quality lenses will safe you allot of trouble.

Sounds like a hack but using teflon tape on the loose aixiz threads makes adjusting smooth and easy. Once you have a good focus ( i set my target at about 200 ft) epoxy the lens in place.

I agree better lenses are good. I think there is a price/ performance tipping point when using lots of diodes though.

[edison]

If you need mounts for collimators let me know. I have bought 20 of these. The baseplate for a quad is worked on this weekend.

The mount will hold a collimator up to 11mm and the beamheight is 20 mm. The flexure mounts of chad are the same height so together they are perfect making a good setup.

[badger1666]

If you need mounts for collimators let me know. I have bought 20 of these. The baseplate for a quad is worked on this weekend.

The mount will hold a collimator up to 11mm and the beamheight is 20 mm. The flexure mounts of chad are the same height so together they are perfect making a good setup.

how much did the mounts cost edison they look quiet nice

[andy_con]

Question for andy_con?

I am curious to the mRad divergence of the roithner lens you use? Also, what diode is used with that lens? With the aixiz glass i can get about .2 -.225 mRad full angle. When i tried using shorter focal length lenses i did get considerable size reduction at aperture but what ever percent reduction at aperture was multiplied in divergence or far field spot size. The roithner lens must be a very special aspherical type. If the far field and near field spot size are proportionally smaller than a simple lens then they would be a god send for increasing the combined beam power density.

although i have 30 roithner 7020h lens, im still yet to even out one on a diode, so i dont know the beam specs yet. but yes im using LOC diodes.

there is a person on this forum who is mega Knowledgeable when it comes to reds and lens. he may see this post and respond during today, if not ill email him later.

do you have any pics of your setup?